MODERATOR'S NOTE:
If you'd like to add to this FAQ, please do the following. Click on the POST REPLY (http://www.avsforum.com/avs-vb/newreply.php?do=newreply&noquote=1&p=6647470) button (don't use the quick reply window). Type the FAQ in the TITLE space. Then answer the FAQ in the message window. I will assemble the questions into the first post of this thread and link each one to the post that contains the question and answer.

OVER-THE-AIR DIGITAL TELEVISION RECEPTION FAQ:

1. Do I need a special antenna to receive HDTV? (http://www.avsforum.com/avs-vb/showthread.php?p=6647479&&#post6647479)
2. How can I find out how much antenna I need? (http://www.avsforum.com/avs-vb/showthread.php?p=6647492&&#post6647492)
3. Do I need a rotator? (http://www.avsforum.com/avs-vb/showthread.php?p=6648155&&#post6648155)
4. Do I need to ground my antenna? (http://www.avsforum.com/avs-vb/showthread.php?p=6649791&&#post6649791)
5. Will OTA digital broadcasts be UHF after analog shutoff? (http://www.avsforum.com/avs-vb/showthread.php?p=6650468&&#post6650468)
6. What are the VHF channels? (http://www.avsforum.com/avs-vb/showthread.php?p=6650533&&#post6650533)
7. What are the UHF channels? (http://www.avsforum.com/avs-vb/showthread.php?p=6650558&&#post6650558)
8. Is a station's digital signal transmitted on the same channel as its analog signal? (http://www.avsforum.com/avs-vb/showthread.php?p=6652048&&#post6652048)
9. If I'm tuning to ch 45 to watch HDTV, why does the display say 7.1? (http://www.avsforum.com/avs-vb/showthread.php?p=6652075&&#post6652075)
10. What's better: more antenna or a pre-amp? (http://www.avsforum.com/avs-vb/showthread.php?p=6650855&&#post6650855)
11. What is "multipath?" (http://www.avsforum.com/avs-vb/showthread.php?p=6650906&&#post6650906)
12. How useful are dish clip-on antennas and other unconventional antenna solutions? (http://www.avsforum.com/avs-vb/showthread.php?p=6692920&&#post6692920)
13. Is analog reception an indicator of how good digital reception will be? (http://www.avsforum.com/avs-vb/showthread.php?p=6742147&&#post6742147)
14. My TV says it's HD Ready. Why can't I tune to any digital stations? (http://www.avsforum.com/avs-vb/showthread.php?p=6763074&&#post6763074)
15. I was getting channel x yesterday, but today it's gone. What happened? (http://www.avsforum.com/avs-vb/showthread.php?p=6763112&&#post6763112)
16. I plugged my HDTV into my cable system and didn't get anything. Why? (http://www.avsforum.com/avs-vb/showthread.php?p=6813246&&#post6813246)
17. Are there other sites I can go to to learn more? (http://www.avsforum.com/avs-vb/showthread.php?p=6692494&&#post6692494)
18. Are there sites other than antennaweb I can use? (http://www.avsforum.com/avs-vb/showthread.php?p=7625830&&#post7625830)
19. What is NTSC, ATSC, QAM and CableCard? (http://www.avsforum.com/avs-vb/showthread.php?p=7770653&&#post7770653)
20. What do I do if my Homeowner's or Condo Association prohibits external antennas? (http://www.avsforum.com/avs-vb/showpost.php?p=15768366&postcount=194)

No. Digital television signals occupy the same part of the television spectrum as analog television signals always have. Any antenna technology that worked for your trusty old television will work for digital. That said, digital is an all-or-nothing proposition. Where you may have been able to live with a fuzzy or ghosty signal on your analog TV, your HDTV may not be able to lock on. You may need more antenna. Depending on how far away from the towers you live, you may can get by with a pair of rabbit ears or you may need to invest in a rooftop antenna.

If you already have an old VHF/UHF rooftop antenna, it should work just fine. You may need to replace the coax running to it and/or add a pre-amp, depending on your specific situation. You can find out more by asking around in your local thread. (http://www.avsforum.com/avs-vb/showthread.php?t=453241)

Start by going to www.antennaweb.org and entering all of your information, or at least your zip code. You'll get a list of all of the available stations, analog and digital, the distance they are from you, the direction they are from you and - in the case of digital channels - the actual channel they broadcast on. The color code provided matches that on the boxes of various antennas. It is only a guide. You may need more or less antenna depending on a host of variables, including terrain, nearby structures and so forth.

www.tvfool.com is another useful site, though a little more technical.

The antennaweb output (http://www.antennaweb.org/aw/Address.aspx) will show if stations are widely separated in azimuth direction; if stations are more than 20 degrees compass direction apart and more than 30 miles away, in general, you will need to adjust your antenna. "High gain" antennas are very narrow in azimuth sensitivity. The half power points (3 db down) even down to 5 to 10 degrees in some cases for very high gain antennas.

If only two directions are of interest, it is possible to "gang" two antennas in different directions but with a 3 db loss and with the possibility of inteference.

Be sure to check your local building codes as these can vary from place to place. Generally though, good information is available at the following:

http://www.mikeholt.com/documents/grounding/word/satellite.doc

http://archive2.avsforum.com/avs-vb/showthread.php?postid=3618667#post3618667

AVSforum member Signal posted the following helpful sites. Dish and antenna masts have the same grounding requirements.


National Electrical Code - Search for "dish" http://forums.nfpa.org:8081/necfaq/necsrch.htm

The information there also applies to antenna grounding. In the 2002 code update, if a water pipe is used, it must be all metal and connected to the electrical panel within 5ft of where the pipe enters the building. The connection to the pipe from the lightning arrestor/ground block and from the antenna/dish mast must also be within 5ft of the pipe's entry.


Preventing Damage Due to Ground Potential Difference
http://www.cinergy.com/surge/ttip08.htm

PSIHQ - Grounding Requirements
http://www.psihq.com/iread/strpgrnd.htm


Probably the most important parts of grounding are to ground the antenna mast and to bond any separate grounding rods to the main building ground. These are safety issues.

VHF and UHF Channels 2-51 are to be used for OTA DTV/HD broadcasting after analog shut off. Current UHF TV channels 52~69 are being reallocated for other uses.

However, the suitability of Lo-VHF channels 2-6 for DTV is currently in question and it may turn out to be the case that very few stations will end up on channel 2-6 after analog shut off.

There are two bands for OTA VHF television channels :

VHF-LO = Channel 2-6 = 54-88MHZ

VHF-HI = Channel 7-13 = 174-216MHZ

Typical outdoor VHF/UHF combo antennas (http://www.kyes.com/antenna/antennatypes/allbandhome.gif) are designed for reception of all TV channels, including VHF Channel 2-13 and usually are also designed for FM broadcast band(88~108MHZ) reception. The longest elements(rods) on the antenna are for reception of VHF-LO TV channels+FM, as the lower the frequency, the longer the wavelength.

There are also VHF/FM "broadband" antennas (http://www.winegard.com/offair/prostar1000vhffmyagi.htm#5030) available designed for reception of VHF TV channels 2-13 and FM, as well as antennas designed for VHF-LO band only, and for VHF-HI band only.

"Rabbit Ears" are currently the most effective VHF indoor settop antenna available.

Note that when seperate VHF/UHF antennas are used, a VHF/UHF joiner is required to combine the antennas if the use of a single feedline is desired.

Current UHF TV band :

Channel 14-69 = 470-806 MHZ

Post-transistion UHF TV band(After analog shut off) :

Channel 14-51 = 470-698MHZ

Note that Channel 37(608~614MHZ) is not used for TV broadcasting, as it is allocated for Radio Astronomy.

Thru years with FM and VHF, I have found that using a bigger antenna and getting more height on same is much better than a pre-amp. From my experience, a pre-amp helps to hold onto the signal you have at the antenna head but does not magically bring in a much stronger signal. In many cases, a rotator comes in very handy to direct the antenna right at the incoming signal. (more) (http://www.avsforum.com/avs-vb/showthread.php?p=6704333&&#post6704333)

Pre-amps do more than overcome line loss, however:
STB's and receivers are not designed with maximum sensitivity in mind. Sensitivity is determined by system noise figure and the average STB is estimated to have a 7 dB noise figure. The better ones today may achieve 5 dB. Add to those numbers a 2 to 4 dB dB cable loss. A properly installed, mast-mounted pre-amp can set the system noise figure to equal the NF of the pre-amp and almost completely negate not only the cable loss but the relatively poor NF of the STB. Instead of of a system NF of 9 to 13 dB we can have with very little work a system NF 2.5 dB. This represents a very substantial advantage to the consumer living 50 miles from a half-power DTV transmitter. While I agree the best place to start for those folks is the highest gain antenna possible, a pre-amp is a legitimate next step for long-range reception regardless of cable loss.

Televes and Winegard and Channel Master all make very good antennas that last a long time. I have a Televes antenna and it looks very handsome as well and very well built. Always buy a little more antenna than you think you need. That extra will come in handy in bad weather. It can not hurt! Happy viewing and listening. By the way, a good place to find out about antennas and to buy them is at 'stark electronics'.

Multipath is a signal taking different routes to arrive at your location. The main signal comes directly from the television station's transmitter to your antenna. But that signal may also bounce off of a nearby building or an airplane flying overhead. That bounced signal arrives at your antenna a split second later. With analog TV, this results in a "ghost;" a second, faint, image to the right of the main image. In digital television, receivers are designed to reject some multipath signals, but strong ones can wreck the signal enough that your tuner can't decode the digital signal. One sign of a digital multipath problem is a receiver that shows full signal strength, but acts as if it's barely getting any.

Directional antennas, like the ones common to rooftops, are designed to reject bounced signals. And some receivers are better at rejecting multipath than others.

A rooftop antenna should be grounded properly and the connections to be weatherproofed as well. (Attic antennas are not required to be grounded). The wire carrying the signal should be checked, maybe, yearly to see that all connections are sound and tight.

Attic antennas (http://www.hdtvprimer.com/ANTENNAS/glossaryA.html#attic) may work if the transmitters are no more than 15/20 miles away. But the attic, itself, may cause more multipath. (Your mileage may vary: some AVS Members have reported solid reception at farther distances using attic antennas) Trial and error is the best thing here. Each installation is different. A clean line of sight is important to the transmitters, of course. UHF antennas work for UHF stations and VHF antennas work for VHF stations. In some areas, you may need a combo antenna since some digital stations in those areas may be on VHF frequencies.

No. Stations have been assigned a separate channel for their digital broadcasts. Each TV station has two transmitters. One for analog and one for digital.

The actual channel number corresponds directly to a 6MHZ wide range of frequencies that is used by the signal. It is also the channel number referred to in the "Frequency Assignment" column in the results for your location from www.antennaweb.org.

It is sometimes important to know the actual channels for your local digital stations. Two of those reasons are :

#1). So you know whether to use a UHF, VHF or a combination of VHF/UHF antenna(s).

#2). In order to "scan in" an individual station so your receiver can use it, some receivers require you to input the actual channel number. Some receivers will also allow you to tune directly to the "actual" channel via direct access tuning to access the programming, either via a Major channel number, or a major/minor channel number combination, such as "28.3". Note that the minor channel x.3 in this case reffers to a MPEG2 program stream number.

With analog OTA reception, The "actual channel number" for any given analog station is what we are used to directly tuning to. For example, WNBC-TV analog in New York, NY transmits on VHF channel 4(66~72MHZ), and OTA viewers in NYC area tune their analog TV directly to channel 4 to receive them.

With digital OTA reception, WNBC-DT(digital) New York, NY currently actually transmits on UHF channel 28(554~560MHZ). Or, another way to say it would be WNBC-DT transmits on RF(Radio frequency) TV channel 28. But, with most receivers, viewers will need to tune to a virtual remapped channel 4.1, or 4.2 to watch programming from WNBC-DT. For more info, see "9. If I'm tuning to ch 45 to watch HDTV, why does the display say 7.1? (http://www.avsforum.com/avs-vb/showthread.php?p=6652075&&#post6652075). "

Note that after analog shut off, some digital stations will be moving to a different channel than they are currently transmitting on. For example, at the current time, KABC-DT, Los Angeles, CA is broadcasting digitally on UHF channel 53, but will switch their digital transmissions to VHF channel 7 after the DTV transistion is complete and analog shut off occurs.

Within their signal, digital stations send channel remapping info via something called "PSIP". PSIP stands for "program and system information protocol" -- see here for more info : http://www.psip.org/ . Note that stations can, and do send quite a bit more info besides virtual channel remapping info via PSIP, such as Time/date info as well as Electronic programming guide.

In most cases, the virtual "remapped channel" number is the channel you will see displayed on your TV, when you tune to a local digital/HD station, and in most cases is the channel you'll tune to in order to watch that station.

In most cases, in discussions on AVSforum the virtual, "remapped channel" number is usually what we use when we list digital station channel numbers, and is also what is referred to in the "channel" column in your results for your location at www.antennaweb.org.

Virtual channel remapping via PSIP allows stations to keep the channel branding which exists for their current, analog station even though the actual channel* the digital station is broadcasting on is different currently, or may be a different actual channel number after analog shut off occurs. It also allows viewers to use the same channel number for the digital station they are used to using for the analog station.

* - For more info See 8. Is a station's digital signal transmitted on the same channel as its analog signal? (http://www.avsforum.com/avs-vb/showthread.php?p=6652048&&#post6652048)

An important thing to remember is that the "remapped channel" is a "virtual channel" and has nothing to do with the actual channel/frequency the digital station is broadcasting on. Therefore even though it may appear when you tune to say, channel 4.1 that you are tuning to a VHF channel, the station may actually be broadcasting on a UHF channel/frequency and the tuner in your receiver/set is actually "tuning" not to channel 4, but to the actual channel the station is broadcasting on, even though it displays "4.1" on the screen.

For example, WNBC-DT(digital) New York, NY remapped channel is 4, although WNBC-DT actually transmits on UHF channel 28(554~560 MHZ).

Also, with Digital TV, "remapped" channels are displayed in the following format :

[ X.x ] X = Major remapped virtual channel number, and x= minor remapped virtual channel number .

A station will have one major remapped channel number, and, with multicasting can run several different program services on several different minor channel numbers. For example, WNBC-DT New York has the following remapped virtual channels :

4.1 for NBC/NBC HD/WNBC programming
4.2 for NBC "weather Plus"

In most cases the remapped major channel number will be the same as the analog station's channel number. For example, WNBC-TV(analog) transmits on VHF channel 4(66~72MHZ), WNBC-DT(digital) remapped major channel number is also 4, even though the digital station actually transmits on UHF channel 28(554~560MHZ).

One problem with virtual channel remapping is that an OTA only DTV receiver must be getting a "good enough" signal to acheive a signal lock from the station in order to receive the PSIP information from the station in order for the channel remapping to be accomplished. So, in some cases it can be difficult, and cumbersome, to adjust the antenna for reception of different stations while only using the "autoscan" feature of the receiver to "find" stations in your area. However, luckily, most, if not all receivers do have the capability to allow the user to either :

#1).Tune manually directly to the channel the station is actually broadcasting on via "direct acess tuning".

#2). Access a "channel edit" screen that will allow you to manually select actual channel numbers for broadcast stations in your area so that the PSIP info from the station will be "saved" when you achieve a signal lock on the station of interest.

#3) Via a menu option, to specify the Actual channel number the station is broadcasting on in order to "scan in" the station so you can view the signal meter on the receiver while adjusting antenna accordingly, or an option that will allow you to add/scan in a number of "new" channels without deleting previously "scanned in" channels.

It is often necessary to have these options not only for adjusting your "rabbit ear" antenna, but also so you will be able to "scan in" stations in different directions from your location given for example, the use of a directional antenna with rotor.

Another tool for locating stations near you:
http://www.2150.com/broadcast/default.asp

Here's a page that discusses putting up antennas:
http://www.hdtvprimer.com/ISSUES/erecting_antenna.html

You can find general information on how antennas work and a glossary of terms here:
http://www.hdtvprimer.com/ANTENNAS/types.html

Agree with Pat and of course it would have to be carefully worded. Don't want Doc to have to fly back from New Dehli to defend the Forum against a suit filed by high priced antenna lawyers. ;) ;) ;)

And separately have to say it: Pat's 2nd cited link seriously undercuts mileage once in a while possible using attic antennas (with no qualifiers).

For analog reception, a lot of these antenna solutions work well, mostly because the signals they're designed to receive are largely VHF. Analog televisions are also very forgiving. A weak signal can look a little fuzzy. A slight ghost isn't that bothersome. But digital television is an all-or-nothing proposition. Instability in the signal can result in no picture at all. For this reason, dish clip-on antennas, "whole house wiring" antennas and other unconventional solutions may not work well with digital television. For more information, see section #2 here:

http://www.kyes.com/antenna/antennadex.html

The things that always bothered me about clip ons is they are relatively low gain folded dipoles which are size dependent for best frequency fit, and are bidirectional but cannot be aimed.

For richard korsgren: In reference to your post #9. There can be situations where a antenna with a narrow beam patten will be desirable. This will usually entail a larger antenna with higher gain. If one has overload problems with a higher gain antenna the overload problem can be remedied by inserting a pad (6-12 dB) in the line.

PS - A compliment to the thread and all the post- Very Good Work

-----------------------------------------------------------------------------------------------------------
Wendell R. Breland • Retired Technical Services Supervisor MAETV - MPB (http://www.mpbonline.org) • Click Red or Green Below For More Info

It appears this FAQ is as complete as it's going to get, so I'm retitiling the thread.

Thanks, everyone, for your input!

Doc

It can be, but not always.

Some DTV stations are running at low, or reduced power, which makes it hard to tell since the analog station is running full blast. Some stations have their DTV antenna much lower on their tower or on a different tower altogether.

Still others have analog and digital channels at different ends of the band. An analog station at UHF22 may come in rock solid while its DTV signal at, say, UHF-62, won't.

Then there's the case of VHF analog stations with UHF digital counterparts. In those cases, analog reception is no guarantee of digital reception at all.

I'd go with a directional outdoor antenna, mounted as high as possible, and try a DTV tuner from a source that has a good return policy.

Bottom line is you have to try it to know.

(Originally posted by Ken H in another thread)

HD-Ready sets are just that - ready to receive HD programming from another source throught DVI, HDMI or component cables. They have no internal digital tuner needed to receive and decode OTA signals. An external Set-Top-Box is required.

If you're shopping for an HDTV that doesn't need a set-top box, look for "HD Built-in" or "built-in ATSC" tuner. ATSC is the digital standard used by over-the-air broadcasters. Don't trust the ads. Google the make and model number to see if the set you're interested has a built-in ATSC tuner. Better still, check the appropriate Displays (http://www.avsforum.com/avs-vb/forumdisplay.php?s=&daysprune=&f=9) forum right here on AVS.

Note that a "built-in NTSC" tuner only means that the set can receive standard analog television broadcasts.

If you were receiving a station that you don't normally get, the atmospheric conditions that helped you get the signal yesterday have changed.

If the station is one you are supposed to get, there are a few possibilities.

1) The station is having a problem. Consult your local thread in the Local HDTV forum.

2) Your antenna is having a problem. This is unlikely if you're still getting other stations properly, but there are some failures that are frequency-dependent.

3) The station has changed their PSIP information. PSIP is a protocol that tells your receiver how the broadcaster is sending the data, as well as including program information. If this changes, some tuners won't rescan the PSIP information when you tune the channel, so they try to find data that isn't organized the same way. Sometimes tuning to the 'real' digital channel (the actual one they're broadcasting on digitally, not the virtual one idenified as x-1) corrects this. For other receivers, you need to do a complete channel rescan.

TVs and Set Top Boxes that exclusively tune over-the-air digital television won't receive HDTV over cable because cable systems use a different system. Broadcast stations transmit using ATSC (http://www.atsc.org/) protocols while cable systems transmit HDTV using QAM. Some tuners (http://www.avsforum.com/avs-vb/showthread.php?t=179095) and televisions will get both ATSC and QAM. Check the specifications in your owner's manual to be sure. Satellite STBs will not receive QAM. Some cable systems encrypt some or all of their HDTV signals, so even QAM tuners won't display the channels. For that, you'd have to use the cable company's STB or a cablecard equipped STB or HDTV.

Conversely, you can't hook the cable company's STB up to an antenna to receive over-the-air HDTV for the same reason.

(clarifications welcome)

Not sure if you want to add this but I wrote a short little article with pictures of an example.
http://www.hdbeat.com/2006/01/30/ota-hd-demystified/

In addition to bdraw's excellent article, Here are a couple more links concerning #17 that some folks might want to look at(probably moreso the article in Sound+vision mag ) :

HDTV over the Air, from Sound and Vision Magazine(page 1 of 3) (http://www.soundandvisionmag.com/article.asp?section_id=2&article_id=738)

I dunno about this one -- It keeps talking about "High definition" antennas<yikes!>, although otherwise it seems OK ...

An introduction to High Definition Off air antennas from about.com (http://tv.about.com/od/hdtv/a/hdantenna.htm)

4/3/06 Update :

Here is A blog of a TV antenna design engineer at Winegard. In addition to several other articles related to DTV transision, there are several excellent articles concerning OTA digital reception :

OTA HDTV Reception Q&A (http://otahdtv.blogspot.com/)

Also, several excellent articles on OTA reception and antennas can be found in the "HDTV antennas and Reception" section in Right sidebar here :

http://www.hdtvexpert.com/

Updated; Magnetic Declination link changed and site updated

This is a complete 'HowTo' use the site '2150.com':

I've done this many times for individuals that are having issues receiving stations or have no idea what/where they are or even if they are within range.
It's too bad AntennaWeb always gets referenced. It's no doubt for it's 'simplified' interface. I find it VERY lacking, failing for these reasons:
1. Most that come to an internet forum are not your average 'joe sixpack' and can comprehend something better then just simple color charts.
2. No idea how/where those results come from.
3. It gives you no data for transmitter output or antenna height which tells you nothing.
4. It is sponsored by the CEA which is only in the business to sell you something.
There is also a new site called TVFool. It appears to have potential, but it's a shame the graphs and pie charts are way too small, cluttered and very hard to read.

Just a few initial steps are all that is needed to have a far superior list for your local stations. It even includes Canada, where that 'other' site doesn't seem to know the country exists. :rolleyes:

Step 1; Go here and enter your zip code, then click 'search' (it will give your approximate coordinates);
http://geocoder.ibegin.com/geolive.php?location=Nuevo+Leon

Step 2; Do a copy/paste of those coordinates watching exactly what you copy. Include the '-' in the longitude with no spaces before either number and then go here;
http://www.2150.com/broadcast/default.asp

Step 3; Select how you want the search to be configured. Choose the distance you want to cover and be sure to check "Include Expired Records" and "Include Construction Permits"! I check also "By distance".

Step 4; To be really accurate you need to find the magnetic declination of you location. A zip code should is sufficient. The results now include a map with a compass showing magnetic north and true north;
http://www.ngdc.noaa.gov/geomagmodels/Declination.jsp

Step 5; Click on "Compute Declination" and do a C&P to the space provided at the 2150 site (default is -13.25) and click on "Show Stations".

Step 6; If you are satisfied with the results you can 'save' this list as a bookmark by clicking on the "Bookmark this link to save this report" link which will bring up another window. This way, all you have to do is refer back to this bookmark (after you saved it in your bookmarks) and all your data is there.

Special notes to interpret what you see;

Column 3; Channel, the first is the actual digital channel, the one in () is the original analog number. Unfortunately, this doesn't show if the station will be reverting back to their original channel next year.
Column 10; HAAT (Height Above Average Terrain) this isn't just the tower height, but a combination of thatheight and the average elevation of the surrounding area. ERP (Effective Radiated Power) is not the transmitter output, but the combined gain and loss of the system.
Column 11; The circle with the dot in the center is the transmitter location, NOT your location! Where that red line meets the outer circle is YOU!
Aim your antenna at the center.
Column 12; If you click on that image, it will show you a map of the trnnsmitter location. Please note, the city stated for the licenesse is rarely NOT where the xmitter is actually located. Sometimes being 30 miles away.

Hope this helps................

From a post elsewhere by Ken H:

TV / Digital TV / Cable / DBS
Tuners 101

In addition to old style analog TV, there are three ways to receive Digital TV and HDTV; over the air (OTA), cable, and DBS. Here is a rundown on the various types of TV tuners available:

NTSC = Legacy analog TV
Receives VHF and UHF band, which determines antenna type required. Found in select HDTV's, select DTV tuners, select DBS tuners, CableCARD, PC cards.

DTV = Over the air Digital TV, which includes HDTV
Receives VHF and UHF band, which determines antenna type required. Found in select HDTV's, CableCARD, stand alone DTV STB, CableCARD, PC cards, USB tuners. Also known as ATSC tuner, HDTV tuner, 8VSB tuner.

QAM = Cable modulation system for DTV
No antenna required, just hook up cable to tuner. Most all cable systems offer the local HD channels they carry 'in-the-clear', viewable with a QAM tuner. Digital tier HD (ESPN HD, Discovery HD, etc.) and premium HD (HBO HD, Showtime HD) are almost always encrypted and not available to view with a QAM tuner. Found in cable STB's, CableCARD, select DTV tuners, PC cards, USB tuners, and select HDTV's. No DBS. Note that not all cableco's carry all the available local HD on their systems, which is when a DTV tuner and antenna would come in very handy.

CableCARD = Conditional access card for cable TV
Cable companies supply for a monthly fee, usually $5 or less. In some areas a CableCARD is included with the programming subscription. The CableCARD goes into a CableCARD host device, like an HDTV with CableCARD compatibility, or the discontinued Sony HD DVR's. Once installed, you receive all cable subscribed channels without a cable box; analog, digital, HD, premium, etc. The downside of a CableCARD is that it can not provide pay per view, video on demand, or interactive program guide; all of which are available with cable HD STB and HD DVR (HD recording ability). CableCARD tuners also include QAM, DTV, NTSC tuners. No DBS.

Cable Set-Top-Box (STB) = A cable QAM tuner with conditional access
Receive all subscribed cable channels. No NTSC, DTV, DBS. CableCARD not needed.

Direct Broadcast Satellite STB = Either a DirecTV or Dish Network receiver or DVR
Receive all subscribed DBS channels, and also includes an DTV tuner (with the exception of the new DirecTV H21 receiver and HR21 DVR). Some include an NTSC tuner. No QAM, CableCARD.

Recent posts regarding antennaweb.org accuracy have been split into the following thread: http://www.avsforum.com/avs-vb/showthread.php?p=7922281#post7922281

Old New Kid On The Block: I'm so old I listen to FM and watch 'regular' TV. Hey, what do you expect from a guy who is currently restoring a '58 Afla Spider for a client? Recently bought a (used) 27" Sony Trinitron WEGA. Seller and his friend set it up, I added an indoor antenna, and it worked superbly. Now, depending (apparently) on how the planets align, some stations come in great, other's suck beyond major sucking. I'm between 9.2 and 9.9 miles from all of the major antennas on Mt. Wilson (So. Cal). Bought an indoor VHF/UHF/HDTV programable antenna from Radio Shack (please no booing), and set it up in the afternoon. By evening everything had changed. I have no (visual) interference from here to Mt. Wilson, yet it is a hit or miss affair when I sit down to watch TV at night. Either a great or lousy picture, depending on the station, and no matter how I adust the antenna.

Is there a way to put in a period so I can get channel 4.1 rather than 41?

I live in an industrial unit and currently have access to my roof (currently being reroofed). What outdoor antenna should I get (though I really don't see why I need one being this close and in line of sight to Mt. Wiilson)?

I've noticed gain control (whatever that is) on Radio Shack antenna makes the picture worse when increasing it.

Went to AntennaWeb. Is the Frequency Assignment supposed to help me in some way?

Would also like to hook up my FM's to the antenna. Dooable? Radio Shacks diplexer got one star out of five. Not good. I want to split the incoming signal from roof antenna to three TV's and two FM radios. Again, dooable?

Went to AntennaWeb. Is the Frequency Assignment supposed to help me in some way? Higher the frequency the less range (usually). But why not get the full story here (three posts up);
http://www.avsforum.com/avs-vb/showthread.php?p=7625830&&#post7625830

Interesting map of DTV penetration. Might be useful to some. The link is to the PDF of a report on the digital transition.


http://img.photobucket.com/albums/v637/keenanj/SP32-20070118-110001.gif

http://www.mbc-thebridge.com/media/archives/Digital_BR011607.pdf
Digital_BR011607.pdf (application/pdf Object)

New Mexico has over 20 digital channels anywhere in the state?? :rolleyes:

That map is by DMA, I'd imagine that cable and sat are rather prolific in New Mexico as they obviously can't get those OTA signals throughout the state. Looks to be a lot of areas like that, look at Utah, although they do use translators in Utah. :eek:

Step 1; Go here and enter your zip code, then click 'search';
http://geocoder.ibegin.com/geolive.php?location=Nuevo+Leon


We operate iBegin, and I thought most users would find this of interest: http://geocoder.ibegin.com/downloads.php [the entire US ZIP Code database in an easy to download format]

Ahmed Farooq; I use to use the Tiger server for the lat. and long., but it was too outdated and didn't include Canada. Someone from Ontario pointed me to this which is a nice improvement. My hats off to you and your database.

One thing; when you enter a US zip code, the results on the third line duplicates the Longitude, not the zip code. Canadian Postal codes aren't affected.

BTW; welcome to the forums.

I have a Panasonic plasma with a ATSC tuner and a roof top antenna. Yes I am amazed at how many free digital channels are available but unfortunately like all tuners it is a matter of -aim your antenna for the best trade off - and start tuning. Once tuning is completed I can get some of the Boston channels but there are many more channels that I can not receive as digital signals are very directional. I live closer to Providence RI and some channels are also located in the local cities of Worcester, New Bedford and even up in New Hampshire. If my tuner allowed me to retune in individual channels I could get them all perfectly with a rotator but NO because it is a one scan deal. I then bought a Sat box with built in ATSC tuner for my mother further north and found even the Boston channels were too directional to allow reception of even the big 5 (NBC, ABC, CBS, PBS and FOX) all at once. After playing with the best signal strength for a couple of hours I found I had to give up on getting digital NBC on 4-1 and the CW if I wanted her to get 2-1, 2-2 and all the 44's (-1 thru -4). These still came in as Analog but once the big switch is over she'll actually get less channels than she did with Analog. Perhaps our goverment doesn't care that Senior citizens who can't afford cable or Sat can't tune in the main channels even with a roof top antenna due to the -one scan and your done- issue with the tuners. I assume the discount DTV boxes will work this way. The general public also doesn't know that SD on a set under 27" looks great and they don't need to replace these smaller sets with digital ones (the land fills are filling up for sure) as the digital tuners will make the picture fantastic near DVD quality. The manufacturers should design these tuners to allow moving of the antenna to get the more directional signal. I also found the cheapest rabbit ears worked better than the most expensive amplified set top antenna I could find.

The manufacturers should design these tuners to allow moving of the antenna to get the more directional signal.

Welcome to the world of screwed up U.S. ATSC DTV. It is one of many things wrong with ATSC.

Try this and see what happens: dial the digital channel directly, one that isn't in the tuner's scanned list. Does it allow you to now add it to the known list?

If not, you are going to have to make a list of known channels and their OTA DTV channels.

This is going to be a real mess after the analog shutdown, as the stations do not have to change any of their on-air-look from their current channel number. For example, the local Fox47 can stay Fox47 and indicate their channel at 47-1, when in reality their OTA channel is 11. Anyone manually punching 47 will get nothing and think their tuner is broken. The government doesn't give a rat's ass that this is going to cause problems, just so the stations do not have to redo all of their channel IDs. Yes, it will cost a shitload of $$$ to change everything, but so many people that do not have a clue how DTV actually works are going to be pissed.

UPDATE: Some of the new CECBs allow multiple scans, i.e., point the antenna in direction A, scan, then repoint the antenna in direction B and scan again. The newly found channels will be added to the list. Check the manual as to what the scanning capability is of the receiver. Unfortunately CECBs only output 480i, as the purpose is to allow DTV reception for analog only TV sets/monitors. HDTV sets, or STBs, might have this capability. Be sure and check the specs, or the manual, before purchasing said device if you need to add channels that won't be found via an initial scan.

VeryFewforums; Welcome to the forums.

Most of the newer sets have the ability to "add channels after a scan" unlike the earily sets that couldn't. With some, all you do is either enter in a two digit number as you would for an analog channel or enter it with the first subchannel to let the tuner know you are looking for a 'digital' channel (66.1 as opposed to just 66).
Other tuners also have the ability to do a "add channels" type of scan where it will rescan without erasing the orginal channel list.
Some sets will actually add channels when they are off that have TVGOS. Examples are Samsung and now Mitsubishi. Though it is annoying with CATV service as all those damn 'switched video' VOD channels magically appear that only have to be deleted later, since they are not 'in the clear' stations.

The best sets actually have two RF inputs so as to allow OTA and CATV channel lists. Now, why doesn't every set have this?
Penny wise, pound foolish............

I'm in probably the most fortunate area in the US because of being within reach of Toronto. I have many of their stations & networks with programming that isn't on American TV. In another 15 months or so, I expect to have more available as the three 'problem', overly strong analog local stations will go dark. In another four plus years it will get better as Canadas' analog stations will do dark which should give me even more, as their low power digital stations that are sharing the limited resources (antennas) on top of the CN tower will be able to go full power.

Some of may stations are SE of me, the rest are NW. I know how you feel by trying to choose which direction to face an antenna to do a one time scan. What you can try is rotating the antenna while the tuner is doing it's scanning. That should give you more chance to add 'borderline' channels if you are unable to 'add' channels that way I described.

It took the Asians a couple of years to realize this. Why would anyone assume every OTA station was from the same direction in the first place?? This 'hidden' feature is usually very poorly documented, if at all. Most sets seem to have this ability now.

Step 2 (optional); Click on the arrows in the upper left hand corner to fine tune your location. You should be able to get your latitude and longitude down to a couple of hundred feet by clicking on you exact location (if you wish).

This doesn't work. The latitude/longitude doesn't update as you navigate the map. iBegin can't find the address, but it can find my zip code. I can find my address on the map, but no dice on getting the proper latitude/longitude for it.

Yep, your right. I never noticed that. I use to use Tiger Server, but that didn't include Canada or the newer zip codes.
This solved those two issues, but creates a new one. :mad:
I have updated my "How to".

GoogleEarth displays lat/long ANYWHERE in the world.

It is too involved and takes too long (compared to the provided links) to get to where you want to be.

It took the Asians a couple of years to realize this. Why would anyone assume every OTA station was from the same direction in the first place?? This 'hidden' feature is usually very poorly documented, if at all. Most sets seem to have this ability now.

I'm not very well versed on how the Japanese system is setup, much less other Asian countries, but in countries that "multiplex," such as the UK, there is essentially no need for a rotor in most places. For digital, the UK system uses 6 UHF channels broadcast from a single tower in each respective area (at least for the 80 main digital towers).

My Sony TV allows me to add digital channels. Even my cheap Westinghouse 19" has this ability. However, for older sets that don't, this is going to be a problem in most areas of the US. LA is one of the few markets that has a good co-location setup.

For digital, the UK system uses 6 UHF channels broadcast from a single tower in each respective areaFine. Thats' ok for over there, but that isn't the case in the US.
Just as they wouldn't put 'scart' connectors in equipment sold in the US, design the stuff so as to use it here to the full extent.

It's actually pretty simple to get your latitude and longitude from Google Maps. Enter your address, then when it shows up on the map click on "Link to this page". Copy & paste the URL into Notepad (or your favorite editor), and look for parameter &ll=xx.xxxxx,yy.yyyyy embedded within the URL. The x's are your latitude and the y's are your longitude (either one could be positive or negative depending on your location).

Now, can someone explain me my results from 2150.com please: http://www.2150.com/broadcast/default.asp?latitude=45%2E493202&longitude=%2D73%2E810551&magnetic_north=%2D14%2E933&range=150&sort=channel&show_expired=True&show_construction=True&show_analog=False&show_low_power=False&action=Show+Stations

Does the above report indicate that I can receive all of those channels? How do I figure out from that report which channels I can catch and where I need to direct my antenna to catch them?

It's actually pretty simple to get your latitude and longitude from Google Maps. Enter your address, then when it shows up on the map click on "Link to this page". Copy & paste the URL into Notepad (or your favorite editor), and look for parameter &ll=xx.xxxxx,yy.yyyyy embedded within the URL. The x's are your latitude and the y's are your longitude (either one could be positive or negative depending on your location).

Now, can someone explain me my results from 2150.com please: http://www.2150.com/broadcast/default.asp?latitude=45%2E493202&longitude=%2D73%2E810551&magnetic_north=%2D14%2E933&range=150&sort=channel&show_expired=True&show_construction=True&show_analog=False&show_low_power=False&action=Show+Stations

Does the above report indicate that I can receive all of those channels? How do I figure out from that report which channels I can catch and where I need to direct my antenna to catch them?

At best, it means you MIGHT receive them. First, take a look at the status column. The ones labelled application or construction may not be operating yet, although the data could be enough out of date that they are. Edit: This based on data in FCC database about Canadian stations. It is probably badly out of date, and forwarded for "coordination" by the Canadian radio authority.

The distance and direction columns tell you how far away it is and what direction. You may want to sort on distance and use a more realistic max. distance. You probably WON"T receive channels 150 miles away.

ALso look at the Effective Radiated Power (ERP column). If it is a low power station, you are not going to receive any great distance.

I resorted your list by distance and limited it to 90 miles;
http://www.2150.com/broadcast/default.asp?latitude=45%2E493202&longitude=%2D73%2E810551&magnetic_north=%2D15&range=90&sort=distance&show_expired=True&show_construction=True&show_analog=True&show_low_power=False&action=Show+Stations

You might be able to get the PBS station in Plattsburgh, but I would forget about those stations in Burlington, unless both you and they are up very high and there isn't anything in between.
Those 14 stations listed less than 12 miles from you, are any on the air yet??

I resorted your list by distance and limited it to 90 miles;
http://www.2150.com/broadcast/default.asp?latitude=45%2E493202&longitude=%2D73%2E810551&magnetic_north=%2D15&range=90&sort=distance&show_expired=True&show_construction=True&show_analog=True&show_low_power=False&action=Show+Stations

You might be able to get the PBS station in Plattsburgh, but I would forget about those stations in Burlington, unless both you and they are up very high and there isn't anything in between.
Those 14 stations listed less than 12 miles from you, are any on the air yet??
Actually, a lot of Montreal folks on the Montreal thread are able to catch all the stations that broadcast from Mt Mansfield with a CM 4221 pointed southwards. That being said, I'm not sure the 2150.com results are very realistic or indicative of what's possible.

I'm not sure the 2150.com results are very realistic or indicative of what's possible. Unlike AntennaWeb, 2150 doesn't 'guess' at your results, it only presents facts and it's up to you to interpert them.
It's as "realistic" as the FCCs' database is.

TVs and Set Top Boxes that exclusively tune over-the-air digital television won't receive HDTV over cable because cable systems use a different system. Broadcast stations transmit using ATSC (http://www.atsc.org/) protocols while cable systems transmit HDTV using QAM. Some tuners (http://www.avsforum.com/avs-vb/showthread.php?t=179095) and televisions will get both ATSC and QAM. Check the specifications in your owner's manual to be sure. Satellite STBs will not receive QAM. Some cable systems encrypt some or all of their HDTV signals, so even QAM tuners won't display the channels. For that, you'd have to use the cable company's STB or a cablecard equipped STB or HDTV.

Conversely, you can't hook the cable company's STB up to an antenna to receive over-the-air HDTV for the same reason.

(clarifications welcome)


I think you just answered my question, but I'm not sure, so I'll ask anyways ;)

Forgive me - I'm a noob with this HDTV stuff (only 2 days into it!).

I have a TV that picks up the digital and OTA HD channels just fine (using 20+ year old bow tie antenna). I'd say that I can pull 26 digital channels with about 7 of those being the local network HD broadcasts.

Relative a few miles down the road has the same TV and similar antenna, but cannot receive the HD local channels. He can only pull 9 digital channels (channels 30 and 66). The only differences are that he is running his antenna through his Directv dvr box, his house is only 1 level (vs 2 levels for me), and his house is also in a flight zone and a couple of feet below street level.

Would the Directv box cause the loss of any signals? The TV has the HDTV tuner, so I'm wondering if that is the issue?

He seems dead set against mounting an antenna on the roof. Is there a decent antenna that will work in the attic?

Is the problem the Directv box, the location of his house (below street level and in a flight zone), or both?

If it helps, I'm west of Washington DC, so all the channels should be coming from the same general direction (as most of the local channels are a few blocks from each other).

Thanks for any and all help!

Is the problem the Directv box, the location of his house (below street level and in a flight zone), or both? Could be all three. And maybe some other problems, too, specific to his location. Without being there, I can't vouch for multipath issues from nearby structures.

Airplanes definitely cause a multipath issue. You can see it on an analog station as the picture flips and moves and gets all kinds of ghosts. For that reason, locations near airports do better with directional antennas that'll reject that interference.

Doc

(PS.. might want to look into deleting that account and starting a new one with a different name. Speaking as a Mod, we're probably not going to let that one stand for very long). Doc

Could be all three. And maybe some other problems, too, specific to his location. Without being there, I can't vouch for multipath issues from nearby structures.

Airplanes definitely cause a multipath issue. You can see it on an analog station as the picture flips and moves and gets all kinds of ghosts. For that reason, locations near airports do better with directional antennas that'll reject that interference.

Doc

(PS.. might want to look into deleting that account and starting a new one with a different name. Speaking as a Mod, we're probably not going to let that one stand for very long). Doc

Okay. Thanks for the fast reply.

The house is probably 16 miles from the airport, but it is considered in the flight zone (going back 8-10 years when you needed that to get satellite and local channels).

I guess we'll just have to try a couple of different antenna and see what we come up with.

Very informative post - have spent the past hour or 2 reading up on the antenna information. I realize that putting the antenna in the attic will reduce his reception. I'm trying to talk him into mounting it on the light post at the side of his driveway! Told him the higher we go, the better the chance of getting a better signal.

I'll take the name change into consideration. It appears there is another user with the same name already here (minus the "." in between) as well as another variation.

Why do HD antennas exist then if they aren't needed?

Why do HD antennas exist then if they aren't needed?There is no such thing as an HD antenna or HD cable or digital antenna/cable. Antennas and cables receive and carry signals, digital or analog format. HD and digital labels for them are marketing devices and have no real meaning.

He seems dead set against mounting an antenna on the roof. That reasoning (if you call it that), has always escaped me. Seems to indicate some type of 'snob' level. Relative a few miles down the road has the same TV and similar antenna, but cannot receive the HD local channels. He can only pull 9 digital channels (channels 30 and 66). The only differences are that he is running his antenna through his Directv dvr boxWhy 'loop' an OTA antenna through a satellite box? Connect it directly to the TVs' RF input. going back 8-10 years when you needed that to get satellite and local channels). Needed "that"?? What an antenna? Nothing has changed in 10 years. Why do HD antennas exist then if they aren't needed? Huh???? What/where did you ever get that idea from????? The "HD" part is only marketing hype. Remember the "Color Approved" antennas from the 60s'??

I'm a newbie and am confused about hooking up OTA:

I have a new Syntax HDTV 537H with built in ATSC. ON the back of the TV there is only one coaxial input called HDTV/Ant. Currently I have my DirecTV Non-HD STB-Receiver plugged into the HDTV/Ant coaxial on the TV. To receive OTA-Local HD would I have to manually unplug the STB-coaxial and plug in a set of rabbit ears or equivalent antenna into the HDTV/Ant -input on the TV? and then search for the signal each time. Is there a way I can use both DirecTv NON-HD STB and OTA? and how would I hook it up. The DirecTV STB I have does not have HDMI or component outputs that you find on the DirecTV HD-STB.

Is there a way I can use both DirecTv NON-HD STB and OTA? and how would I hook it up. The DirecTV STB I have does not have HDMI or component outputs that you find on the DirecTV HD-STB.

Does the D* box have any outputs other than RF out? Does it have S-Video or Composite? Those are not ideal, I know, but if it works...

What channel is the D* box outputting to? An open question I have is whether combining say channel 3 from the box with OTA by a simple splitter would be one possible solution? If 3 (or 4) are not used locally, perhaps this would work, though I doubt it would be an ideal solution.

My DirecTV STB receiver (D* box?) indeed does have S-Video and Composite out. Are they both superior to the Coax-out/RF on the (D* box?) or is only S-Video superior? If S-Video is superior to the Coax-out/RF-out signal would you suggest that I use S-Video for my standard Def and use RCA cables for the audio? and then use a set of rabbit attached via coax to the HDTV/Ant in on the TV? Many Thanks Falcon and others.

Currently I have my DirecTV Non-HD STB-Receiver plugged into the HDTV/Ant coaxial on the TV. Wrong! That went out with VCRs' in the 80's (or should of with the availibility of 'montior' type TVs' (direct inputs).
Use the S-video out to your TV. whether combining say channel 3 from the box with OTA by a simple splitter would be one possible solution? Absolutely not. It's not that easy. That channel three would have to be 'injected' into the antenna feed.

Uh OH, below says S-Video could be worse than RF coax when using an HDTV. Does this make sense:

http://www.highdefforum.com/archive/index.php/t-5913.html

Ok thanks videobruce!

My DirecTV STB receiver (D* box?) indeed does have S-Video and Composite out. Are they both superior to the Coax-out/RF on the (D* box?) or is only S-Video superior? If S-Video is superior to the Coax-out/RF-out signal would you suggest that I use S-Video for my standard Def and use RCA cables for the audio? and then use a set of rabbit attached via coax to the HDTV/Ant in on the TV? Many Thanks Falcon and others.

Yes, I would suggest giving S-video a try. It should be better than the RF out, depending on the quality of the RF modulator in the D* box. Then you can hook up the antenna to the RF in and have both D* and OTA with a change of inputs on the TV remote.

Sounds like a plan and thanks guys for your help! I'm approximately 25 miles from the HDTV tower. IYO can you guys recommend an indoor antenna from Radio Shack that would work? Are these HDTV antenna's overhyped and would plain rabbit ears suffice?

hoarybat; That TV and thread is almost 2 years old. It was probably that "like $50" cable he used. :rolleyes:
(The age usually becomes apparent when the terms "like" and "OMG" are used) ;)

I would recomend not going to RS. They were great in the 70s' and 80s'. They started to slip in the 90s'.
Use to be a great place to get electronic component parts from.
Now, they have very little. I just saw a newer RS natenna and most of the elements were either bent ot broken off. The antenna couldn't of been more than a two or three years old.

Bang for the buck, you can't go wrong here (if you want something small). I have seen it as low as the price of a Silver Sensor ($17).;
http://www.eagleaspen.com/products/products_1.php?id=49

BTW, where are you (Zip)?

Thanks videobruce but thats an indoor antenna? looks more like an outdoor.

You can use it anywhere you have room. It should fit in a closet.
The orginal 'big' brother is here;

Does the D* box have any outputs other than RF out? Does it have S-Video or Composite? Those are not ideal, I know, but if it works...

What channel is the D* box outputting to? An open question I have is whether combining say channel 3 from the box with OTA by a simple splitter would be one possible solution? If 3 (or 4) are not used locally, perhaps this would work, though I doubt it would be an ideal solution.
CH3/4 signal going into RF Splitter will leak across to OTA antenna input and be radiated throughout
the neighborhood....thereby possibly interfering with your neighbors and can violate FCC regulations.

You would need an RF Switch if you pursued this approach.

S-Video or Composite (Yellow cable) would be the preferred approach.

It's actually pretty simple to get your latitude and longitude from Google Maps. Enter your address, then when it shows up on the map click on "Link to this page". Copy & paste the URL into Notepad (or your favorite editor), and look for parameter &ll=xx.xxxxx,yy.yyyyy embedded within the URL. The x's are your latitude and the y's are your longitude (either one could be positive or negative depending on your location).

Now, can someone explain me my results from 2150.com please: http://www.2150.com/broadcast/default.asp?latitude=45%2E493202&longitude=%2D73%2E810551&magnetic_north=%2D14%2E933&range=150&sort=channel&show_expired=True&show_construction=True&show_analog=False&show_low_power=False&action=Show+Stations

Does the above report indicate that I can receive all of those channels? How do I figure out from that report which channels I can catch and where I need to direct my antenna to catch them?
www.2150.com/broadcast does not PREDICT which channels you can receive.

Unfortunately, www.antennaweb.org predictions do not work outside U.S.A.

However, you can use www.tvfool.com to PREDICT reception.
Attachment below shows both NTSC analog and ATSC digital channels.

Nearest stations are about 10 miles away, so try without an amplified antenna.
You may or may NOT improve distant performance with a Preamp---you could try
a low-gain, high overload type such as the W-G HDP-269.

You'll probably get most if not all of the "LOS" (line-of-sight) stations, but can
expect difficulty with "1Edge" and "2Edge" stations due to intervening terrain.
Be sure to visit TVFool web site for information on how to interpret these charts.

Yes, I would suggest giving S-video a try. It should be better than the RF out, depending on the quality of the RF modulator in the D* box. Then you can hook up the antenna to the RF in and have both D* and OTA with a change of inputs on the TV remote.

Most definately. Plus, I seriously doubt that D* even bothered to use a MTS (stereo) modulator for the audio. Even if they did, that is inferior to the direct baseband audio that is available on the audio out jacks.

www.2150.com/broadcast does not PREDICT which channels you can receive.
Unfortunately, www.antennaweb.org predictions do not work outside U.S.A. 2150 isn't suppose to "predict" anything. No one can do that. As far as antenna web, their "predictions" don't amount to much inside the US.

There may not be an answer to this one:

I live about 60 miles east of LA - without cable or satellite - and use an RS 15-2187 HD antenna to grab the OTA signals. All the networks' digital broadcasts are currently on the UHF band and we get crystal clear reception (except for Channel 13). Is there any way to tell what is going to happen to my reception in 2009 once analog goes away and some (all?) of the digital signals revert from UHF back to VHF?

There may not be an answer to this one:

I live about 60 miles east of LA - without cable or satellite - and use an RS 15-2187 HD antenna to grab the OTA signals. All the networks' digital broadcasts are currently on the UHF band and we get crystal clear reception (except for Channel 13). Is there any way to tell what is going to happen to my reception in 2009 once analog goes away and some (all?) of the digital signals revert from UHF back to VHF?
Since the new DTV coverage is "supposed" to replicate the number of existing analog users,
a good guess is to simply see if you can receive the analog channels.
Of course, you may find you need a "real" hi-VHF antenna.

Since many Sat Receivers don't DO analog, try it with the analog tuner in either a TV, HDTV or VCR.

Well, for the record - and not surprisingly - for Channels 2 (CBS), 4 (NBC) and 5 (CW) my analog reception is relatively poor; and for Channels 7 (ABC), 9 (Ind), 11 (Fox) and 13 (MN) the reception is actually pretty decent. (And it is still not clear to me why we get the analog signal for 13 and not the digital.)

I guess that means that if the networks follow the FCC (strong?) suggestion of staying away from 2 thru 6, I shouldn't have issues... :rolleyes:

And it is still not clear to me why we get the analog signal for 13 and not the digital.

Might it be because the digital channel isn't on VHF-13, but on a UHF channel?

I guess that means that if the networks follow the FCC (strong?) suggestion of staying away from 2 thru 6, I shouldn't have issues... :rolleyes:

In a majority of the cases, the networks have nothing to do with a station's request to go back to the analog channel for digital, even if the station is a network O&O. Local engineering might have a pretty big say as to determining if the station reverts or not. A station that is an affiliate of a network will determine on their own, and/or in consultation with the parent company, what they requested (revert or not).

In some cases, the station wasn't allowed to revert, which happened in my area.

That reasoning (if you call it that), has always escaped me. Seems to indicate some type of 'snob' level. Why 'loop' an OTA antenna through a satellite box? Connect it directly to the TVs' RF input. Needed "that"?? What an antenna? Nothing has changed in 10 years. Huh???? What/where did you ever get that idea from????? The "HD" part is only marketing hype. Remember the "Color Approved" antennas from the 60s'??

Truly I don't know the reasoning behind not wanting an antenna on the roof - they already have a Directv dish on the roof!

"Looping" through the box was really just an oversight on my part. I was rushing to try to get everything hooked up. I'm not as knowledgable about HDTV and digital signals as I'd like to be. This is my first experience with HD and digital signals (always had D* or E*).

Another consideration was trying to avoid having to retrain the user on how to view their programming. It was bad enough having to hook up the D* box and DVD to 2 different inputs (tuner & component) and trying to teach them which input to select. Moving D* to composite and OTA to tuner might have pushed them over the edge. I have since given him a switch to split the D* and OTA signal into the tuner input. I'm waiting to hear back if it was successful.

"That" was referring to the "old days" of needing a waiver to receive network channels via satellite (back in the Primestar days). Living in a flight zone they've always had difficulties receiving OTA signals. They've had satellite (starting with Prime*) since I've known them, so I don't know what they did before that.

I'm trying to convince them to just upgrade their D* service to HD, but they don't want to lose pricing and special programming left over from Prime*. Last time they tried to add a $5.99 channel they were told their programming had to change - they would lose east/west coast network channels and add a total of $16-17 to the monthly bill.


As I'm sure you are aware, not everybody happily accepts these new changes. Some people need to be dragged, kicking and screaming!

Well, for the record - and not surprisingly - for Channels 2 (CBS), 4 (NBC) and 5 (CW) my analog reception is relatively poor; and for Channels 7 (ABC), 9 (Ind), 11 (Fox) and 13 (MN) the reception is actually pretty decent. (And it is still not clear to me why we get the analog signal for 13 and not the digital.)

I guess that means that if the networks follow the FCC (strong?) suggestion of staying away from 2 thru 6, I shouldn't have issues... :rolleyes:
The upper channels have higher cable/RF Splitter losses and perhaps also lower antenna gain.....

I punched 92350 zipcode into www.tvfool.com and see that digital KCOP-DT (13.1 MyN on ch66)
is two channels above nearby KSGA (ch64, 2-3 miles away).
This strong station is probably preventing reception of the weaker KCOP-DT.
KTTV-DT (11.1 FOX on ch65) is on an adjacent channel, but is about 6 dB stronger.

TVFool presumes omni receive antennas and calculates that KSGA is about 20 dB stronger than KCOP-DT.
Because it probably isn't in a sidelobe null (typ. +/- 30 degrees from max), the antenna can
only provide moderate gain suppression towards KSGA.

ATSC A/74 Performance Guidelines (based on various tests) indicate that
a digital station can be WEAKER than an adjacent analog station by about 35 dB (+/- 5 dB) and
next adjacent (N +/- 2) channels by about 40 dB (+/- 10 dB, depending on desired signal levels).
However recent FCC OET 07-TR-1003 tests revealed that tested HDTV's were actually slightly MORE
sensitive to interference from next adjacent (N +/- 2) channels as from adjacent (N +/- 1) channels.
Hence 13.1 may be MORE sensitive to interference than 11.1.

Never the less, stronger KSGA "shouldn't" prevent reception of KCOP-DT due strictly to adjacent
channel considerations. However, AGC "capture" by the stronger station as well as non-linear
intermodulation distortion products may still be a problem.

You may be able to add additional suppression towards KSGA by installing a chicken-wire "fence" in your attic.
Keep it as far away from the antenna as possible to minimize perturbing the antenna pattern.....
Since you can receive KTTV-DT, maybe you only need a little more suppression.

BTW: You really need to also tweak the antenna back and forth to see if you can
"steer" a null towards KSGA....

============================
05Dec07: CORRECTIONS are in BOLD

Note: if following is getting a little too "in depth" for this thread, Doc/mods by all means feel free to edit or remove the following post :


TVFool presumes omni antennas and calculates that KSGA is about 20 dB stronger than KCOP-DT.


Don’t mean to split too fine of a hair here, as that explanation “works” ...

However, think it is important to note TVfool predictions do not actually presume anything about performance of receive antenna. They are predictions for the signal level as it exists in "free space” at a optional user specified height, which of course is also “omnidirectional” in nature, so to speak …

But, the transmit antenna performance/directional pattern(if any) is taken into account by tvfool predictions. The ERP value given in the plots is directly related to this.


ATSC A/74 Performance Guidelines (based on various tests) indicate that an adjacent analog station should be WEAKER than a digital station by about 35 dB (+/- 5 dB) and next adjacent (N +/- 2) channels by about 40 dB (+/- 10 dB, depending on desired signal levels).


The –35db in for N +/1 (given -53dbm signal level for desired signal) refers to the “Desired” signal for the desired to undesired(D/U) ratio expressed in A/74 document, as well as elsewhere as described in more detail below ...

While you’d think given the way they express it as “NTSC interference into DTV” they “mean” the opposite .....

Actually, in the ATSC A/74 document, table 4.2 indicates a receiver meets A/74 guidelines if it can successfully decode a desired DTV signal w/o impairments if the desired DTV signal is -35db weaker than the undesired 1st adjacent channel analog station given the desired signal level is at -53dbm. -40db weaker desired DTV signal than a NTSC analog at N +/- 2 with desired signal level at -53dbm.

I think The D/U ratios as expressed in :

#1). ATSC A/74 document

#2). FCC’s OET bullitin #69, and rules such as are specified regarding applications/changing DTV allotments for various channel relationships here in CFR 47, Sec 73.623 ( http://www.hallikainen.com/FccRules/2007/73/623),

#3) in the FCC OET 07-TR-1003 report entitled “Interference Rejection Thresholds of Consumer Digital Television Receivers Available in 2005 and 2006” :

Is well described in the “Executive Summary”/Interference Rejection section on page ix of OET-07-TR-1003 report, somewhat near beginning of the document as quoted below (I’ve bolded the portion of this of most interest, but thought it necessary to include the rest of these 2 paragraphs in the quote ) :


INTERFERENCE REJECTION TESTS

The out-of-channel interference rejection threshold of consumer digital television (DTV) receivers was measured by supplying an ATSC 8-VSB* signal (the desired signal), along with one or two undesired signals, to the antenna terminal of a DTV receiver and then adjusting the level of the undesired signal(s)to the point at which picture degradation begins to be observed—a point known as the threshold of visibility (TOV) of degradation. In such testing, the DTV receiver is tuned to the channel number of the desired signal. The undesired signal (the potential interferer) is placed on another channel, either above or below the desired channel.

We refer to the desired signal power at the input to the DTV receiver as D and the undesired power when adjusted to the threshold (TOV) as U. It is traditional to express interference rejection performance in terms of the ratio D/U. When D/U is expressed in decibels (dB), it is typically a negative number for out of-channel interference; that is, the undesired signal level is greater than the desired signal at TOV. Low values (i.e., large negative numbers) represent good rejection performance; high values (small negative numbers) represent high susceptibility to interference. D/U ratios measured for this report ranged from below -74 dB to -20 dB. Results in this report are presented both as D/U ratios and as threshold values of the undesired signal power U in order to meet the needs or preferences of different analysts.


And, this short quote from the same report should also further clarify this :


“Consider the case of a D/U ratio of -60 dB—meaning that the desired TV signal power is 60 dB below the
power of the interferer .... "


Otherwise, it would make no sense whatsoever that FCC has allocated in some cases some 1st adjacent channel DTV+NTSC channel allocations in the same market, even squriting RF off the same stick(tower) for that matter, as is case the for stations such as WCPO 9 analog/WCPO-DT 10 Cincinnati, in my area ..... check tvfool signal predictions for those two stations for 45042 .... For my location, it predicts -74.3dbm for WCPO-DT 10, -60.1dbm for WCPO 9 analog ... Since these broadcast from the same tower(316Kw ERP analog “peak” power on 9, 16.3KW ERP “average” DTV power, both with non-directional antenna patterns) obviously they are in same direction .... Obviously, the signals are generally of the same or similar *relative* strength(between each other) for everyone in their service area, and yes, it seems it works just fine with all my receivers with the DTV signal, say, around -14db or so below the NTSC N-1 signal ….. (Hopefully that's the case for everyone in the area, but I can't say) ...



However recent FCC OET 07-TR-1003 tests revealed that tested HDTV's were actually slightly MORE sensitive to interference from next adjacent (N +/- 2) channels as from adjacent (N +/- 1) channels. Hence 13.1 may be MORE sensitive to interference than 11.1.


Indeed, a summary in chapter 5 of those results indicate it is true at low tested signal levels(+3db above threshold for desired signal) suspectibility to interference from N +/-2 signals being worse than N +1/-1 is pretty much the cases for all the receivers(which was unexpected, it seems) they tested. But, the report also summerizes that only 2 of the 8 receivers tested “worse” on N +/-2 than N +/- 1, and one more worse on N+2 only at somewhat higher signal levels (for desired signal) …

If you look at table A-5 (appendix A), for the resuts with Desired signal at -53dbm, the median D/U among all the receivers actually beat the ATSC performance guidline by 1.5 db, and the best performance was –49db D/U, 9db “better” than ATSC A/74 … OTOH, the worst receiver is shown with –27.4 db D/U, 13db WORSE than A74 guideline, and a whopping 22.5db difference in performance between the best and worst receiver !

The summary of “Rejection performance” on page x is also interesting, it notes that no receiver tested fully achieved ATSC A/74(which is “less stringent than the receiver performance assumptions on which current DTV interference protection criteria are based” (I.e. OET bulleitin #69 ) ... With the best-performing receiver tested failing only on one channel offset, and there by only 1db … I’d certianly like to know which receiver that is, especially given the poor performance on some channel offsets by some of the worst performing receivers tested ? (as much as 24 db “worse” than A74 !!) …. For that matter, I'd like to know the makes/models/etc of all those receivers tested ;)

While I appreciate your efforts, Jeff, most of it is in fact lost on me. I knew it was going to be a challenge when I came to a site called "AV Science Forum".

That said, I understand what holl_ands means when he says that tvfool "assumes" an omnidirectional antenna. To me, that has nothing to do with performance (how well it receives), only that tvfool will tell you what signals the location in question is capable of receiving, regardless of direction.

I also understand that there is a nearby signal on Channel 64 (4.2 miles away, at 250 degrees from true north) that may be interfering with a weaker, more distant signal on Channel 66 (50 miles away, 285 degrees from true north). So if I rotate my antenna a few degrees to the north, I might be able to reduce the interference from the signal from KSGA (Channel 64) that may be keeping us from receiving KCOP (Channel 13.1/66).

I am still not clear on how to apply the chickenwire screen solution. Do I surround the antenna (with as large a radius as possible)? Or do I only erect it as a "shield", leaving an opening on the northwest quadrant to accommodate the signals from Mt. Wilson? Or is there a third option? For the record, my antenna is facing WNW, approximately 12 feet from the west, gable end of our house.

Again, as a layman I appreciate the many good things on this site. And at least this thread doesn't get as nasty as some of the discussions comparing LCD to plasma. :eek:

That said, I understand what holl_ands means when he says that tvfool "assumes" an omnidirectional antenna. To me, that has nothing to do with performance (how well it receives)


In terms of directivity(and a true Omnidirectional antenna which has none), certianly.

An Omnidirectional(or any) receive antenna has performance characteristics(such as gain) which are not modelled by TV fool, most signal "predictions"(such as what FCC does) are based on certian performance charactieristics of receive antennas used, that's all I was saying.

I only brought it up because it was not "exactly" clear to me whether or not he was refering to transmit antenna(which *is* modeled whether it's omnidirectional or directional) or receive antenna, I assumed he meant receive antenna but wasn't sure ....


.... only that tvfool will tell you what signals the location in question is capable of receiving, regardless of direction.


Yes, certianly ....


I also understand that there is a nearby signal on Channel 64 (4.2 miles away, at 250 degrees from true north) that may be interfering with a weaker, more distant signal on Channel 66 (50 miles away, 285 degrees from true north). So if I rotate my antenna a few degrees to the north, I might be able to reduce the interference from the signal from KSGA (Channel 64) that may be keeping us from receiving KCOP (Channel 13.1/66).


I wonder what a polar plot for the RS 15-2187 Looks like? Specs on it on radio shack website indicate that whatever sort of antenna it actually is, it is apparently inside a radome ... and the RS specs show 1/2 power beamwidth on UHF is 60 degrees, which means it's directivity is not very good, and a station 30 degrees(1/2 of the 1/2 power beamwidth, which would extend 30 degrees on each "side" of where antenna is aimed) from direction antenna is aimed should only be rejected by about 3db (1/2 power) ... so with antenna aimed around 60degrees or a little more "away" from KSGP, it's possible you may perhaps(just a wild guess really) be getting around say, 10db or so rejection of KSGP-LP signal with your antenna aimed as it is, although that should really be enough(actually, No rejection of it should really be enough), I'd think.

Another "interesting" spec on 15-2187 on RS website shows average Front back ratio of 17db on UHF .... If anywhere near being true, that's actually pretty good, as usually with directional antennas(such as yagis), you have bigger nulls "off the side" of antenna than off the back ....

Keep in mind, KSGP-LP is a analog, Low power station. If the predictions from TVfool were absolutely "correct", based on FCC tests of various, recent DTV receivers this really shouldn't be a interference issue(even with use of a omnidirectional receive antenna) , as the predicted signal difference of 20db more undesired signal from KSGP-LP 64 than the desired KCOP-DT 66 signal is less difference than the worst performing receiver FCC tested these channel relationships for, and signifcantly less than the best performing receiver, for which the KSGP signal could be approximetely 29db stronger and reception of KCOP-DT could still be acheived ....

HOWEVER, the tvfool dbm values are predictions which are based on F(99,99) curves, and it very well may be the case that the signals you're actually getting may be significantly stronger than the predictions in dBm show, which will of course be even stronger with the gain added by your antenna/amp.

Of the receivers FCC tested for interference rejection given a desired signal level of -68dbm(the closest "in the ballpark" figure to your TVfool predicted KCOP-DT 66 signal of -63dbm via a "zip code" plot), The *worst* receiver tested was able to achieve DTV reception with a 2nd adjacent(N +2 signal) 28db stronger -- that should hopefully be pretty much be a "worse case" scenerio, and the best performing receiver on this test could withstand a N+2 signal 50db stronger than the desired signal+still acheive reception, the median of all receivers tested was a -41db D/U ratio ....

While KTTV-DT 65 (-57.2dbm) is predicted to be 6db stronger by TVfool(and these are only predictions, keep in mind), at signal levels for the desired signal of -53dbm, Most receivers tested by FCC, as one would expect performed worse in interference rejection tests with a 1st adjacent channel interfereing signal. The best performing receiver tested acheived reception of the desired signal with the desired signal as much as 40db weaker than the lower first adjacent channel(N-1) - 9db "worse" than the best receiver for the 2nd adjacent channel (N-2) tests -- and the median of all receivers was a -41.5db D/U ratio (almost exactly the same as N -2 test) ... But, the worst receivers did perform significantly better(by about 7db than N-2 tests) ..

Now, if the signal levels are actually signficantly higher than Tvfool predictions(lets say about 20db higher at receiver input), as you might predict, the receivers selectivity becomes worse per the FCC tests. With the desireed signal at -28dBm for instance, the receivers tested all had D/U's of about -26db for lower 2nd adjacent channel interference, and D/U's of about -21db for lower 1st adjacent channel interference ... Meaning the interfering signal caused DTV reception of desired signal to drop below threshold at these higher signal levels if the desired signal was at or more than 21db weaker than a 1st lower adjacent channel signal, or 26db(or more) weaker than a 2nd lower adjacent channel signal. *IF* however this was the case, then I would expect your KTTV-DT 65 signal to be non-receivable or have reception related "glitches" as well as KCOP-DT 66 ....

And, generally speaking, even though it is predicted as 6db stronger than KCOP-DT, Assuming you are getting good reception of KTTV-DT(digital) on 65, I'm skeptical concerning interference from KSGP-LP being the issue of concern, here(even if you were using a omnidirectional antenna, although that might cut things pretty close depending upon what the deired signal level actually is), and you certianly shouldn't need 55db less signal from KSGP-LP than KCOP-DT.

If there is a "interference" type issue involved, (rather than something else such as multipath or weak signals if the amp isn't working/isn't being powered properly/etc - note - in most cases, if a amplifier is unpowered, the unpowered circuitry in the amp will attenuate signals *greatly*, much much more than if the antenna wasn't amplified) ..... If anything, I'd suspect it may be more likely to involve the tuner/amp being overloaded(because your using an amp where there are some fairly strong signals around) .... I don't know anything about the real "specs" of the amp in that RS antenna, just based on what I do know (10db gain) if your going to use an amp, that would be the sort of "specs" you'd probably want in your sitatuation.(although, actually, you really shouldn't need a amp at all given the predicted signal levels involved, unless you need it for distrubution to various devices) ... But generally speaking, High power station KVCR(analog+digital) would probably be the biggest concern (unless perhaps there may be very nearby FM stations or other sources of RF not on TV band frequencies which could still overload things and cause IMD (intermodulation distortion) .....


I am still not clear on how to apply the chickenwire screen solution. Do I surround the antenna (with as large a radius as possible)? Or do I only erect it as a "shield", leaving an opening on the northwest quadrant to accommodate the signals from Mt. Wilson? For the record, my antenna is facing WNW, approximately 12 feet from the west, gable end of our house .....


My guess is going that route may involve quite a bit of experiementation(which may or may not yield any positive results) ... But basically, If you want to increase rejection of KSGP-lP, seems to me you would want to put the screen generally Southwest of the antenna, and you wouldn't want it between the antenna+Mt Wilson .... - As holl_ands said, perhaps in the attic would work ....


Or is there a third option?


If I were you, FWIW, I might consider trying an unamplfied antenna that offers better performance(especially better directivity) than the antenna you are using, then adding an amp later if necessary or desired ....

Although, OTOH, of course, as you've already noted, KCOP-DT will be moving to ch 13 in 14 months, so you might not want to put too much "effort" into it(and if you do you don't want to "concentrate" only on UHF, as you'll want to make sure your Hi-VHF reception remains good), as chances are very good that if you receive good analog reception on Hi-VHF(ch 7-13) as you've reported, the same will be true for the digitals, including KCOP-DT 13 ....


Again, as a layman I appreciate the many good things on this site.


I do hope I've explained the above "clearly enough" for it to be at least somewhat understandable(I'm doing my best, which is all I can do !), there are many factors which can effect OTA reception, and it can be very "complicated" to post about it and try to "guess" what may be causing any given reception problem in any given case, and even more complicated(and difficult) to post about it in "plain english" without writing a "book" so to speak ! .....

Jeff:

I can say that I am comprehending at least 75% of what you're saying and, for what I need to know, that is more than enough. I did not spend a tremendous amount of money on this antenna, but it does suit my needs. What you say regarding its "directivity" makes sense, and what you suggest about the chicken wire confirms my thinking on that as well.

Appreciate your help and your thoughts.

Glenn.

Oh bother!!! I've stumbled into the negative D/U rabbit hole....knowing full well...after all it was right in plain sight!!!!

I corrected the post above (in BOLD).
Adjacent and Next Adjacent Channels "shouldn't" be causing problems.
But further analysis would be needed to address non-linear intermod effects and related AGC Capture effects
(strong signal can desensitize and reduce dynamic range for desired signal, esp with multipath).

=================================
Firstly, get the antenna up off the (signal sucking) attic floor and give it half a chance of working by aiming it.

For the 92350 Post Office location, Mt Wilson is towards 285 degrees True North (272 Magnetic)
and KSGA is towards 224 degrees True North (211 Magnetic).
Hence Mt Wilson is 75 degrees to "left" of True North and KSGA is 61 degrees further "left" from Mt Wilson.
[You should punch your address into www.tvfool.com to refine these numbers....]

An antenna with a "nominal" 60 degree beamwidth only approaches that for lowest channels.
For upper channels they (and probably also the R-S) would have much narrower beamwidth.

Suppose we assume the R-S is "similar" to the CM-4221 wrt beamwidth:
http://www.hdtvprimer.com/ANTENNAS/cm4221.html
It may approach 60 degree beamwidth for CH20, but is closer to 40 degree beamwidth for CH60.
And is about 20 dB down at +/- 60 degrees and hence should significantly suppress KSGA.

================================
To mount the antenna in the attic, a simple metal or plastic pipe (Sked 40, either 1-in or 3/4-in) can be
attached from an overhead rafter (see post #64 above and below attachment), so the antenna
can be twisted back and forth to aim it.

Once you've figured out which way is "North", eye-ball where you think Mt Wilson is and then OFFSET the
antenna from about -45 degrees to +45 degrees in perhaps 15 degree increments, having someone write
down how well each position works for 2.1, 11.1 and 66.1 (13.1)...a signal percentage display helps.
[Before your HDTV acquires "synthetic" 13.1, you'll need to punch in the REAL channel on 66.1]

holl_ands:

The mounting hardware for my antenna is sitting safely in my garage. I understand that I took a very lazy route and basically just "threw" the antenna up in my attic space. It IS pointed in the general direction of Mt. Wilson, but I will elevate it and rotate it from side to side to see what happens. Ultimately, I know that my reception will be no worse than it is now.

Thanks.

Glenn.

KCOP-DT (13.1) was the only station I couldn't get at my son's location (attic, East of Murrieta, 75 miles from Mt Wilson).
But since there was/is nothing worth watching in HD on MyNetwork, I haven't had any reason to try anything different....

If you check the L.A. Thread, you'll see that numerous people have problems with KCOP-DT...and don't really care....

My wife and I talked about it and we couldn't think of a single thing we watch on KCOP, either.

By the way, my antenna is now mounted on a platform in the attic space, using the arm and bracket that came with it. I have not done any further adjusting, but if KCOP is all we're missing, we aren't missing much.

OT, but An HD airing of "Cider House Rules" and a HD Bikini show (both were aired last season) are the only things I've watched on MyTV, LOL ...

Nightwatchman;

Thanks Jeff, for the D/U explanation in message 75. Somehow, in the trades they seem talk all *around* the topic without clearly stating what you did that one message.
tnx agn
Kelly

I have an Olevia 232V 32" HDTV (built in tuners for OTA) and am trying to get OTA digital broadcasts. I am in NNJ. This is actually my son's, but I am borrowing it from him. I last used it at the end of the summer it could pick up fox (5.1), and channels 41 and 50/51. Now it can only get 41, 51 and 68 after a scan. Scans were done on both air and cable settings.

Trying to better understand the real issue here I have been doing some research. I have used antennaweb.org to determine potential stations. I gather from some of the posts on this site that there are those who do not feel this is a reliable resource; however, I believe it is good enough for my purposes as I am close to the source, no real interference issues, and get excellent OTA analog signals.

Most of the channels, according to antennaweb.org, are coming from the same direction (160 degrees, which if I understand this correctly is 20 degrees east of south). This seems to explain 41 and 68, but 51 comes from 212 degrees. Thus it appears the antenna has a significantly wide range.

All the major stations and independents (2, 4, 5, 7, 9, 11, 13) are listed at the same distance and direction, so I assume their antennas are located together, but I can't get a one of them in. They are in the same direction and distance as the ones I can get. I tried manual entering in the actual frequency into the TV, but it can't find the signal. I find it incredibly difficult to believe that the majors have a weaker signal then these lesser stations.

I am at a loss to make sense of this, perhaps someone can comment on this.

How far away are you from the stations that you're trying to receive? What type or model of antenna are you using? Indoor or outdoor? It would help if you posted your antennaweb.org results, or better, from tvfool.com (which provides more technical information). Also, use your actual address or coordinates instead of just your ZIP code for input, if you haven't done so already. Parts of northern NJ are rather hilly or even mountainous, which can definitely affect reception.

According to AntennaWeb I am within 20 miles of most of the stations. I am using a roof mounted antenna and do not know the manufacturer. I am located near Paterson before the hills and have a pretty straight line of site to NYC. I can get excellent analog reception and thus have never felt the need to get cable.

I used the street address and checked the street level map for correct location. How would I post my AntennaWeb results?

I ran the search at TV Fool. It gives similar info as AntennaWeb. It seems to show that I shouldn't have any problem getting a digital signal.

Hi all. I built an HTPC a week ago and this weekend put a Channel Master Advantage 3020 directional antenna into my attic with the smallest CM preamp attached (I couldn't find a Spartan 3 preamp that wasn't missing parts).

A large, directional antenna with preamp was recommended to me by antennaweb.org. My zip is 75028. Nearly all stations (and all that I care about) are at 163-164 degrees at a distance of 32 to 35 miles. I could have gone with the next-smaller antenna, but went with this one "to be sure".

Before this, with a small, unamplified antenna attached to my DirecTV dish I was getting:

1. ABC affiliate at channel 9 (only VHF digital station) showed very spotty performance. Weak signal strength (35%) and frequent loss of picture ("stuttering").
2. No reception of local independent station at channel 18. Low power transmitter that I wasn't able to get even with my TV's built in tuner.
3. Good performance on most other stations, although all showed signal strength of no more than 40-45%. Local FOX affiliate at channel 35 would cut out every now and then.

After the antenna and preamp installation I am seeing a bit of a slip in performance:

1. All channels now show signal strength of above 50% with some up to 75-80%.
2. ABC affiliate comes through solidly with no stutter.
3. I can now receive IND station at channel 18 with no apparent problems.
4. FOX affiliate, however, now shows more stuttering than before. Signal quality seems to be down vs. what I was seeing before.
5. My CW affiliate at channel 32, which I received fine before, is *extremely* unstable and can't lock onto a good signal at all.

My general question is: "What should I try next"? HMA rules don't allow me to put this monster antenna on the roof, and I currently have it in the only space where it reasonably fits in the attic. There is, I am sure, some interference from the roof/shingles/gutters that I am contending with.

Here is my short list of options:

A. Ensure antenna is pointing at 163 degrees. Currently pointing is estimated, so perhaps a more direct point would help.
B. Try the antenna without the preamp. Could I be overpowering the problem signals? This seems unlikely.
C. Get the better preamp. Could this help?
D. Perform some adjustment on the antenna. I am not sure other than pointing what I can do here. The setup does not appear to have anything on the UHF end that can be adjusted. Anyone else with this antenna may know more.
E. Given that my problems are with channels 35 and 32 it could be that the FOX affiliate is masking the CW one. Is this possible and how would I correct for it.

My experience with this sort of thing is fairly limited, so any help would be greatly appreciated.

My first suggestion would be to try reception w/o the pre-amp. In general, I would suggest that all installations be tried without a pre-amp at first. Too much signal can be just as bad as too little. Which pre-amp are you using? At ~31-34 miles from the towers, you should not need a high powered pre-amp.

Also, if your amp has a PIM (Power Insertion Module), please be sure to remove both the PIM and the pre-amp from the system. Unplugging the PIM will result in substantial signal degradation. Care must also be taken to make sure that the PIM is directly connected to the Pre-Amp, w/o any splits, etc., in between the two.

Attics have dead spots, which will affect different frequencies in different ways. The 3020 is a good antenna, but from first hand experience, I know how hard it is to move around. I could not connect the VHF and UHF portions in my attic and I eventually removed it. Also, the 3020 owes much of its size to Low-VHF reception, which is not needed in most areas for DTV. WFAA is on 9 for DTV, which only needs a smaller upper VHF antenna. In 2009, WFAA will move back to 8 and be joined by KFWD on 9 and KTVT on 11.

HMA rules don't allow me to put this monster antenna on the roof,.

HMA rules be damned. If you own the house, or renting the house, you are allowed, by law, to put your antenna on the roof. All such HMA rules were struck down by law.

Just show them the following document:

http://www.fcc.gov/mb/facts/otard.html

If they threaten to sue, tell them to get their wallets out, because they will lose.

Just show them the following document:

http://www.fcc.gov/mb/facts/otard.html


I would like some clarification on this:

The rule applies to video antennas including direct-to-home satellite dishes that are less than one meter (39.37") in diameter (or of any size in Alaska), TV antennas, and wireless cable antennas.

Does the 40" measurement only limit satellite dishes? In other words, are Yagi type antennas with boom lengths over 40" protected as well?

I had previously read this as to preclude antennas over 40" in any dimension to not be subject to the rule, but perhaps that is not the intent. If anyone can clarify, it may change my thinking at some of my sites.

With the physical size requirements for VHF antennas, the 40" limit did not seem appropriate.

Does the 40" measurement only limit satellite dishes? In other words, are Yagi type antennas with boom lengths over 40" protected as well?

The 40" rule is for satellite dishes. OTA antennas for broadcast TV reception can be whatever size it takes to get the signal. There is a height restriction though, which you will probably not hit.

Antennas for any other use, AFAIK, are not protected.

I am using the Channel Master 3039 preamp, the low end of their offerings, primarily because it was the only one I could in stock at 3 Frys stores. (I found a couple of marked-down, ripped-open, 3041DSBs but these were both missing the part that attaches to the antenna!)

I can confirm that the preamp is attached via a single, unsplit or spliced, coax cable.

I agree that the 3020 may have been a bit of an overkill, since I only had one VHF station to worry about (however, that was one of my biggest problems as well). I also agree that the 3020 is a *monster* to maneuver. I am actually quite proud of the positioning I have done so far, but it is completely inflexible to go anywhere else.

For grins I will try the setup without the preamp. The on-roof antenna was not preamped before so this one *should* be better even without it -- that is, unless the attic is causing more problems than I would hope.

I am really going to hate tearing this thing down and returning it if I have to, but I suspect I really didn't need this antenna. If it all works, however, then I won't touch it.

My wife never goes up in the attic. If she saw this thing I can just imagine what her reaction would be :).

HMA rules be damned. If you own the house, or renting the house, you are allowed, by law, to put your antenna on the roof. All such HMA rules were struck down by law.

Just show them the following document:

http://www.fcc.gov/mb/facts/otard.html

If they threaten to sue, tell them to get their wallets out, because they will lose.

Yes, but even I would have to question a 13-foot antenna mounted on the peak of my roof. I did a visual check of the neighborhood yesterday and didn't see a single house with an independent OTA antenna. There were many dishes, and some with small attached antennas. A nearby neighborhood had several OTA antennas, but they were at most half this size (hint?).

I am going to assume for now that the larger size may help offset my in-attic installation. We shall see.

I did a visual check of the neighborhood yesterday and didn't see a single house with an independent OTA antenna. There were many dishes, and some with small attached antennas. A nearby neighborhood had several OTA antennas, but they were at most half this size (hint?).

A majority of TV viewers have cable or pizza-pan dish. So that will reduce the odds of an outside antenna. Also, you association may have bullied your neighbors into believing that the HOA rules were 100% law.

Unlike your neighbors, you have a copy of the federal rules to show that that section of the HOA was struck down.

Again, size doesn't matter. :D

I am using the Channel Master 3039 preamp, the low end of their offerings

I have not dealt with this pre-amp, but with 13dB of gain, it would not seem as likely to overload as a 26dB gain CM7777.


I am really going to hate tearing this thing down and returning it if I have to, but I suspect I really didn't need this antenna. If it all works, however, then I won't touch it.


The best antenna is the one that works, so if you can get it working, there is no need to worry about it being "too big." If it is in a dead spot in the attic and can't be moved... then, that will be a problem.

What is the antenna looking through, the roof or the siding? Knowing the composition of the roof or siding, etc. would be helpful. Do you have any stucco?

What is the antenna looking through, the roof or the siding? Knowing the composition of the roof or siding, etc. would be helpful. Do you have any stucco?

The antenna is looking through the roof, which is standard roof board with composite shingles. There is a vent of some sort running just below the antenna's pointing location which may cause a little interference, but since it is below rather than above I wouldn't think it would be significant.

I think the fact that I am pulling in the hardest-to-receive, lowest-power station says that my antenna location is sufficient. I believe, however, that I may have the antenna pointed a bit to far to the left. I am probably closer to 160 degrees than 170 degrees, and TV Fool tells me that I should be pointed to 169 degrees of "true north". Antennaweb.org gives magnetic degrees, and I don't have a compass handy.

I may try repointing just a bit this evening and see if it helps. One of the very-front dipoles is also slightly bent, so I will correct that since it is likely having some impact. I am certainly learning a lot of interesting stuff about how antennas work....

More Sophisticated Antennas Required

As spending tightens in these uncertain economic times, discretionary purchasing has shifted away from other key market categories, to consumer electronics and particularly to digital TV and HD. High Definition Televisions bumped digital cameras out of the top spot for the most desired CE product for 2007. Several dynamics are affecting millions of households now relying on analog signals for reception of their broadcast TV signals, with antennas older than 2 years. They need to upgrade to the new antenna technology, along with cable and satellite customers looking for alternatives. This has resulted in tremendous sales increases of OTA antennas for Antennas Direct. Although cable and satellite program providers will continue to serve the great majority of homes as the primary signal source, missing HD local reception, higher costs, billing add-ons, service outages, contact difficulties, in-home service waits and no shows have left many subscribers looking to OTA antennas as alternatives and backup.

Richard Schneider, President of Antennas Direct said “Our antenna sales for the first two months of 2008 are up 125% over this time last year, a year that in itself that was up 60% over 2006. The simple fact is that not all antennas are equal, some are better and some are the best for particular reception situations. This shift in consumer spending could not have come at a better time for us, because of the tremendous improvements in our Off-Air antenna technology and design that have taken place in the last few years, allowing us to offer the best OTA antennas for the HD revolution.”

According to an article in Ad Age “As Giant Retailers Reel, Marketers Gird for Worst”, as to Consumer Electronics, the news appears very positive. “Consumers seem to have designated technology as a new necessity, along with food, gasoline and home-heating oil" said the Consumer Electronics Association’s group economist, Shawn DuBravac. Ad Age continued “Forecasts for 2008 from the CEA and other CE researchers such as iSuppli bear that out, with predictions of overall electronics growth.” "Last year, when oil prices were going through the roof, we saw that people said, 'Since we're not traveling, let's spend some of that money on buying a flat-panel TV,'" said iSuppli analyst Riddih Patel.

There are more than 40 million households currently receiving OTA analog signals in the U.S., according to new proprietary research just released by Centris (www.centris.com), a leading market research firm. They said this number represents a “large opportunity for…manufacturers and distributors of "smart" television antennas…requir(ing) …more sophisticated (OTA) antennas.” Centris surveys reveal that 75% or more of over-the-air households have only set-top antennas. “The effect will have extensive ramifications, not only among consumers, but also electronics retailers and manufacturers who can expect an influx of costly returns when it is realized that the converter boxes and new digital TV's don't work," says Barry Goodstadt, Senior Vice President of Centris.

To viewers already receiving a cable or satellite network, the benefits of Off-Air antennas are compelling. There is only so much room on cable or satellite bandwidth in which to squeeze signal, so data is compressed to fit, resulting in a somewhat "soft" picture. An OTA signal is the gold standard in digital reception because it's almost completely uncompressed and also FREE. Local digital TV broadcasts are everywhere. But bandwidth limitations force cable and satellite providers to not carry all local channels in many areas, or may not offer all of them in high definition. Contract disagreements between local cable operators and local broadcasters mean that major networks may not be available in several areas. DISH Network® offers local HD coverage to about 47 percent of U.S. markets, while DIRECTV® reaches about 76 percent, but for an additional monthly fee.

“What about those other millions of viewers who want to see their favorite local shows and in HD” asks Schneider? “The answer is to add an OTA antenna to other signal reception sources”. This not only gives a viewer the ability to receive all their local stations, but, with the right digital antenna and location, some viewers may even be able to receive out-of-town channels, carrying blacked out sports programs or network broadcasts not available in their home town. As an added benefit, an OTA antenna provides back-up reception options for local cable or satellite signal loss due to equipment failure or rain, snow and ice fade and to smaller TVs and second sets in homes not wired for whole-house signal distribution.

No one puts any credence in the Centris study:
http://www.tvtechnology.com/pages/s.0015/t.11299.html

Because the Centris study simply used www.antennaweb.com to predict coverage,
the entire study is bogus...cuz antennaweb is notorious for not finding stations that people
are successfully receiving....

A much more believable study was conducted by andy.s.lee who runs www.tvfool.com:
http://www.tvfool.com/index.php?option=com_content&task=blogcategory&id=17&Itemid=84

Because the Centris study simply used www.antennaweb.com to predict coverage,
the entire study is bogus...cuz antennaweb is notorious for not finding stations that people
are successfully receiving....

Antennaweb really seems to have a problem with ATSC modeling and/or UHF in particular. I don't think they are taking into account the difference in NTSC peak power vs. ATSC average power for starters. Most analog stations for me are listed as "blue," while it only lists 2 DTV "violet" UHF stations. In reality, the UHF DTV stations are stronger than most of their analog UHF counterparts.

Antennaweb needs to make some changes for it to be a credible resource other than to find channel #'s and distances.

Each TV station has two transmitters and two antennas. One for analog and one for digital.

Not always the case. TV stations can end up using the same antenna for both analog and digital transmissions. In most cases this can happen because the channel assignments are right next to each other, or very close. And with today's antenna designs, they don't even have to be close. In my market there are two stations using the same antenna. In this case they are on channels 20/21 and 26/27. In another case, two different stations are using the same digital antenna and their channels are 19 and 32.

Not always the case. TV stations can end up using the same antenna for both analog and digital transmissions. In most cases this can happen because the channel assignments are right next to each other, or very close. And with today's antenna designs, they don't even have to be close. In my market there are two stations using the same antenna. In this case they are on channels 20/21 and 26/27. In another case, two different stations are using the same digital antenna and their channels are 19 and 32.

Yeah, I know that is possible. I think either I said it that way, or Doc edited my post so it said that and demonstrated in a simple, short and understandable way that any particular station's analog+digital channel assignments are different and that different transmitters are used for the digital/analog stations ... In other words, to show They can't/don't both transmit on the same channel, as if you don't understand how they would interfere with each other, it is easy to conclude that they are transmitting on the same channel if all you see is the PSIP VCT(virtual channel table) Major/Minor channel number displayed on your screen.


That being said, most in my area are using different transmit antennas for various reasons, including when they are on first adajcent channel assignments (N+1 or N-1).

I'm certianly fine with that post being edited to be more accurate if Doc wants to edit it/change it.

TV stations can end up using the same antenna for both analog and digital transmissions.

Are you using "antenna" to mean "set of radiating elements" or "tower" (that the radiating elements are mounted on)?

Are you using "antenna" to mean "set of radiating elements" or "tower" (that the radiating elements are mounted on)?

Physical antenna. I know that some call the tower the antenna, but not me (which you wouldn't know unless you've seen other postings of mine, or the web page that I have devoted to the newest tower that was constructed in my area).

That normally pertains to AM radio towers, i.e., tower = antenna :D

I think that the 26/27 station that I referenced was the first DTV station in Wisconsin. Because they were able to use their existing antenna and got a great deal on the 26 transmistter (50% off and beta test site), Madison was an early adopter of DTV. Not that anyone was able to watch what they were broadcasting :D

... as if you don't understand how they would interfere with each other ...

Interfere as in one transmitter possibly blowing out the output stage of the other transmitter :D I haven't looked into the technology, but do combiners keep the RF from one transmitter from feeding back into any of the other transmitters using the combiner? I've never dug into that and asked, since no one in their right mind would try and combine the same channel of active transmitters.

Maybe the posting can be changed to:

Each TV station has two transmitters, one for analog and one for digital. Separate broadcast antennas may not be required, saving the station money in operational and maintenance costs, as the output from the two transmitters can be combined to feed a single antenna.

Interfere as in one transmitter possibly blowing out the output stage of the other transmitter :D


Strange as it may seem, many don't know that, for instance, a digital station which identifies itself as "WCPO 9 Cincinnati" actually transmits on Channel 10, and the analog transmits on 9 (currently) .... I've noticed Some assume that both are transmitting on the same channel .... Such an assumption can be a problem if your receiver doesn't find all your local stations via a "autoscan" and you need to input the actual RF channel # (channel of transmission) for a particular station and adjust your antenna so that a signal sufficent to decode the PSIP VCT info can be acquired.

Keep in mind, The title of this thread is "OVER-THE-AIR-DIGITAL RECEPTION FAQ: New to OTA? Start Here!," not "Everything you wanted to know about our DTV standard or broadcast engineering but were afraid to ask" ... ;)

While certianly interesting to me, to be honest I even doubt that whether or not a station is using seperate transmit antenna for digital is of much interest to most who come to this thread looking for help with their OTA reception. Except perhaps involving issues such as related to a seperate transmit antenna for DTV being on a different stick/in different location, or in some cases is using a different pattern (or beam tilt) --- issues which are probably best addressed in local threads, or perhaps some of the other antenna threads anyway ....


I haven't looked into the technology, but do combiners keep the RF from one transmitter from feeding back into any of the other transmitters using the combiner?


http://www.tvtechnology.com/features/On-RF/f-DL-Combining%20Signals.shtml

http://www.patentstorm.us/patents/6356742-description.html

http://radiomagonline.com/mag/radio_rf_combiners/


Maybe the posting can be changed to:

Each TV station has two transmitters, one for analog and one for digital. Separate broadcast antennas may not be required, saving the station money in operational and maintenance costs, as the output from the two transmitters can be combined to feed a single antenna.


Thanks for the suggestion + input. But, decided to/went ahead and changed it to the following instead :


Each TV station has two transmitters. One for analog and one for digital.


And again, I certianly appreciate your suggestion, but I also think the more you say about these things, in some cases the more "unnecessarily-complicated" it gets for the reader given the subject and purpose of this FAQ/thread. Or to say it another way, the more "other possibilities of interest" besides what has been posted become more releveant.

For example, Some stations in some cases currently use seperate transmit antennas for digital and analog which have different performance charactieristics, and different patterns as well, that can also save the station $ in operational costs, as for instance, the transmit antenna for one or the other may offer more gain. (More gain at antenna=less TPO required = lower bills from the power co ...)

In any case, didn't think about this before, but in a little less than 11 months, we're probably going to want to edit the FAQ info that mentions the analog broadcasts, as it's going to be outdated info as it pertains to full service stations, as there will be no analog NTSC broadcasts from them ....

Anyway thanks again for pointing out this correction ....

Strange as it may seem, many don't know that, for instance, a digital station which identifies itself as "WCPO 9 Cincinnati" actually transmits on Channel 10, and the analog transmits on 9 (currently) .... I've noticed Some assume that both are transmitting on the same channel .... Such an assumption can be a problem if your receiver doesn't find all your local stations via a "autoscan" and you need to input the actual RF channel # (channel of transmission) for a particular station and adjust your antenna so that a signal sufficent to decode the PSIP VCT info can be acquired.

I agree that there are many that do not know there are separate channels for the analog and digital.

It is going to be a lot of fun when viewers are forced to go digital when the analog channels go away. In some situations, the new digital viewer will connect up their new CECB and let it do its channel scan. All fine and dandy for those viewers whose antenna can point in a single direction. For those that had to swing their antenna around to get some other stations, those digital channels might not get scanned. So the viewer swings the antenna around and punched in channel 9 and nothing happens, not knowing that they had to punch in 10 instead. It is going to be a lot of fun after the transition.

I personally believe that the broadcast stations that are assinged new channels be forced to rebrand to remove the confusion over actual verse virtual channel numbers. I fully understand the costs involved with doing that. The expense for going digital is bad enough, without adding to it the rebranding costs.

While I don't know if this will happen or not, but think about the confusion where a new station starts and gets the old analog frequency of a station in the DMA that didn't want to move back to that frequency. Now there really is a channel 32.

Keep in mind, The title of this thread is "OVER-THE-AIR-DIGITAL RECEPTION FAQ: New to OTA? Start Here!," not "Everything you wanted to know about our DTV standard or broadcast engineering but were afraid to ask" ... ;)

Point taken.

Anyway thanks again for pointing out this correction ....

You are welcome and thanks for the links. An interesting read.

i didn't know where to post my question, but since i'm new to OTA DTV, i'll post it here.

i have a zenith dtt900 box connected to rabbit ears and i get great reception to DTV stations as i am an estimated 16 miles from every one. only drawback is that i live near an airport, under a flight path and it causes my signal to drop/pause for about 10 seconds everytime a plane flies by.

i've been looking to build a 2-bay antenna (DB2) for indoor use as i don't want to mount an antenna on my roof. do you think this will help in eliminating the signal drops? also, what is the grill on the DB2 used for?

thanks!

The DTT900 has it's own thread
http://www.avsforum.com/avs-vb/showthread.php?t=948767
And there's an antenna thread
http://www.avsforum.com/avs-vb/showthread.php?t=381623
and an antenna making thread.
http://www.avsforum.com/avs-vb/showthread.php?t=798265

Which, of course, is what makes this the right place to ask. Let me give you a brief response and then go to whichever thread addresses what you want to do.

The DTT900 thread is mainly usage reports, reviews and discussions of that CECB in a variety of implementations, as well as related news. The antenna thread will ask you to use TVFool.com to analyze your local signal field before making commercial antenna recommendations as they will vary with channel and strength. Antenna making is just that, based mainly on 4-bay bowtie variants, and the Gray-Hoverman. You'd be amazed what we use indoors (in closets, in attics, etc.)

I'm not the guy to tell you what airplanes to signal, but I can tell you that rabbit ears are typically low gain and 2/3 omnidirectional (i.e. in 2 of 3 dimensions). One easy way to increase gain is by use of a reflector ~1/4 wave behind the antenna elements. This makes it directional with increased gain coming from the reflected signal. Stacking elements (2-bay, 4-bay) tightens the gain pattern vertically - again more gain with less directionality - so you'd get less signal from aircraft.

My guess is that almost anything that reduces vertical gain will reduce aircraft interference. In the tradition of doing cheap stuff first, I recommend looking at the antenna-making thread as a simple 4-bay bowtie without reflector would be a good upgrade from the rabbit ears. It would yield a flattened gain field that's roughly the same in compass direction, but far more directional in altitude, cutting off anything overhead.
http://www.avsforum.com/avs-vb/showthread.php?p=13508054#post13508054

I'll note that spokybob is doing something unique - making antennas for those on fixed-income who need a little more gain than their rabbit ears provide.

Have fun,
Frank

The Ken H referenced posting about NTSC, ATSC, QAM and Cablecard is in error. The cablecard descriptive entery is correct. But the inclusion of cablecard with NTSC, ATSC and QAM is wrong. The cablecard is not a tuner of any sort. It has nothing to do with any of those "broadcast" formats.

It is an access card and a limited access one at that. I'd love to see how a cablecard works with NTSC, ATSC (8T-VSB) and QAM tuners.

Tech Now! has posted a series of informational videos regarding the DTV transition. To view them, please refer to the bottom of the following link, starting at "Any New TV Will Work":

http://www.technowtv.com/?cat=9991945&subcat=4524034

One comment I have, on the Antenna video, is the lack of UHF bow-tie antennas. The large antenna displayed has Low-VHF elements, which won't be needed for most areas for DTV. A preferred substitute (for areas w/o Low-VHF) would be something like the CM4228:

http://www.hdtvprimer.com/ANTENNAS/cm4228.html

Also, "higher-end" indoor antennas are still far from "outdoor class" and often times, amplified indoor antennas can cause more problems than they solve.

In my Seattle-area condo, I can receive most of the local DTV stations reasonably well. However, on two stations (KOMO-DT 38 and KIRO-DT 39) I've noticed wider signal-strength variations than with other stations in my local market. I'm accustomed to other reception issues in my location, but the KOMO and KIRO signals sometimes come in very stable and at other times fluctuate a lot. I haven't found any analog LP stations which would interfere. Is there any way to determine if unlicensed wireless devices are being used in my immediate vicinity on the same frequency ranges as UHF 38 and 39? http://www.tvfool.com/modeling/tmp/df4fb51875/getdigital.php

Your local SBE (Society of Broadcasting Engineers) coordinates wireless microphone
and other users in the TV bands. If you have difficulty locating them, contact station engineers.

... among other things. But in my area, according to TVFool, the VHF digital stations are staying VHF and one UHF analog station going digital will be joining them there. Net VHF increase of one. One of the existing VHF stations is going Low VHF to higher VHF but none of them are going UHF. Is my area (49024) an exception to the rule? One of the PBS stations is even staying in the low VHF band. p.s. these are main CBS, NBC, and PBS stations in my area.

I think it is safe to say that most stations whose analog channels are in the high-VHF range (7-13) will use those channels for digital after the transition. On the other hand, most stations whose analog channels are in low-VHF (2-6) will use a UHF channel after the transition.

There are exceptions to both cases, of course.

... among other things. But in my area, according to TVFool, the VHF digital stations are staying VHF and one UHF analog station going digital will be joining them there. Net VHF increase of one. One of the existing VHF stations is going Low VHF to higher VHF but none of them are going UHF. Is my area (49024) an exception to the rule? One of the PBS stations is even staying in the low VHF band. p.s. these are main CBS, NBC, and PBS stations in my area.
It doesn't mean VHF is going to UHF. But in practice, many are. Or more specifically, many analog VHF stations had their digital signals placed somewhere on UHF (14-69) and the stations are keeping the channel where the digital signals are now. As a result, stations which used to be VHF entirely will become UHF entirely if they keep their current UHF channel for digital.

Some have to move, though -- channels 52 through 69 are being taken from the UHF TV range and their frequencies sold off for other applications. As a result, our Austin Fox affiliate (analog 7) which broadcasts today on digital 56 will lose that, so they are going back to digital 7 in February.

In reality, an all-UHF world would make it easier to deal with OTA because one strong UHF antenna would likely meet all needs. But absent that, high VHF (7-13) is the next best thing. A few stations are going to be stuck on low VHF (2-6) which is apparently horrible for digital TV. Some stations currently allotted low VHF after 2/17/09 are still scrambling and trying to get exceptions granted with the FCC to allow them to move elsewhere.

The confusing thing is that these stations may keep their analog channel number as part of their identification even if they don't broadcast there - whether VHF or UHF. Here in Austin, for example, channel 42 (analog) broadcasts digitally at 43 and is keeping 43 after 2/17/09. Will they still have '42' as part of their logo? Or will CBS 42 become CBS 43?

Here in Austin, for example, channel 42 (analog) broadcasts digitally at 43 and is keeping 43 after 2/17/09. Will they still have '42' as part of their logo? Or will CBS 42 become CBS 43?

They will still call themselves "channel 42" or "CBS 42" or whatever they're calling themselves now. The FCC requires that stations continue to identify themselves by their "old" channel number (by specifying it as the virtual channel number in their PSIP data), even if they're actually using a different physical channel after analog shutdown.

They will still call themselves "channel 42" or "CBS 42" or whatever they're calling themselves now. The FCC requires that stations continue to identify themselves by their "old" channel number (by specifying it as the virtual channel number in their PSIP data), even if they're actually using a different physical channel after analog shutdown.
Thanks. I hadn't heard that was an FCC mandate.

Thanks. I hadn't heard that was an FCC mandate.

Neither have I. We need a quote from an official FCC reg, stating reg number as well.

I believe the deal was that they weren't required to rebrand, though I personally would prefer that everyone gave their channel number as their REAL channel number, not what they used to be.

In some areas of the country, The given up analog channel will be taken over by someone else. Image a person's surprise when they manually punch in the channel number of a station, thnking they would be tuning in ACBD, instead getting EDGH and wondering why. Or, someone tried to tune in the channel and gets nothing and do not have a clue as to why not.

Sometimes the autoscan doesn't work. A local channel was missed during the autoscan, but when I punched it in the REAL digital channel number, it captured the signal.

I understand the underlying economics of why not, but hate the fact that channel numbers won't mean a damn thing anymore.

We need a quote from an official FCC reg, stating reg number as well.

See this post (http://www.avsforum.com/avs-vb/showthread.php?p=12799241#post12799241) and the subsequent discussion, from a thread in the Local HDTV Info and Reception forum.

Strictly speaking, this applies to the channel designation that appears on a digital TV tuner. I suppose they can call themselves anything they want, in advertising, on-screen logos, etc. Some channels around here don't use their channel number on screen at all, and brand themselves as something like "ABC Columbia" or "FOX Charlotte." For several years, the NBC station in Charlotte branded itself as "6 News" because it's on channel 6 on all the local cable systems, even though its analog broadcast channel is 36. I don't think I ever saw them use the number "36" on screen during this period. It only showed up in a TV tuner's channel display. Now that I think of it, they still don't use "36" on screen, just the call letters WCNC, or the phrase "Carolinas News Connection."

See this post (http://www.avsforum.com/avs-vb/showthread.php?p=12799241#post12799241) and the subsequent discussion, from a thread in the Local HDTV Info and Reception forum.

As I read it, the PSIP channel identification to point back to the NTSC analog channel is for during the transition. I saw nothing in that posting that said one had to continue pointing the PSIP channel identification at a channel that doesn't exist anymore. In other words, I saw nothing to keep a station from rebranding and/or now telling their viewers what their real channel is. Will anyone do it? Probably not.

Strictly speaking, this applies to the channel designation that appears on a digital TV tuner. I suppose they can call themselves anything they want, in advertising, on-screen logos, etc. Some channels around here don't use their channel number on screen at all, and brand themselves as something like "ABC Columbia" or "FOX Charlotte." For several years, the NBC station in Charlotte branded itself as "6 News" because it's on channel 6 on all the local cable systems, even though its analog broadcast channel is 36. I don't think I ever saw them use the number "36" on screen during this period. It only showed up in a TV tuner's channel display. Now that I think of it, they still don't use "36" on screen, just the call letters WCNC, or the phrase "Carolinas News Connection."

Then you need to come to Madison, WI: WISC-TV-3, NBC15, WKOW-27 (27News) and Fox47. Not one of them is getting back their analog channel. I do not know what the CW affiliate does, as I do not watch them and the PBS affiliate doesn't really reference their channel number either. But, 4 out of 6 definately do.

YMMV per location.

As I read it, the PSIP channel identification to point back to the NTSC analog channel is for during the transition. I saw nothing in that posting that said one had to continue pointing the PSIP channel identification at a channel that doesn't exist anymore.

See this post (http://www.avsforum.com/avs-vb/showthread.php?p=12803944#post12803944) a bit further down in that thread.

(added)

I just noticed that the link to the FCC's Second DTV Review in the post that I referenced earlier, actually points to the press release. Here's the actual document:

Second Periodic DTV Review Report and Order (hraunfoss.fcc.gov/edocs_public/attachmatch/FCC-04-192A1.pdf)

The relevant sections are paragraph 153 on page 68, and footnote 359 on the same page.

The channel number rules originate in ATSC standard A/65B. It looks like version B has now been superseded by version C:

ATSC standard A/65C (http://www.atsc.org/standards/a_65cr1_with_amend_1.pdf)

The relevant section is Annex B, section 1, "ASSIGNMENT OF MAJOR CHANNEL NUMBER VALUES FOR TERRESTRIAL BROADCAST IN THE U.S.", on page 90.

Yeah, They updated it to requiring A65/C in 3rd DTV review.

There are more info/details about the channel mapping requirement in the 2nd DTV review, but As for the actual "rule" requiring A65C (as already mentioned and detailed in the text of 2nd DTV review which includes requirement for VCT major Channel = analog channel #) Here is the "actual rule" from CFR 47, Sec. 73.682 (d), I've bolded the part about A65C ... :


d) Digital broadcast television transmission standard. Effective May 29,
2008 transmission of digital broadcast television (DTV) signals shall comply
with the standards for such transmissions set forth in ATSC A/52: “ATSC
Standard Digital Audio Compression (AC–3)” (incorporated by reference, see
Sec. 73.8000), ATSC A/53, Parts 1–6: 2007 “ATSC Digital Television Standard,”
(January 3, 2007), except for section 6.1.2 (“Compression Format
Constraints”) of A/53 Part 4: 2007 (“MPEG–2 Video Systems Characteristics”)
and the phrase “see Table 6.2” in section 6.1.1 Table 6.1 and section 6.1.3
Table 6.3 (incorporated by reference, see Sec. 73.8000), and ATSC A/65C: “ATSC
Program and System Information Protocol for Terrestrial Broadcast and Cable,
Revision C With Amendment No. 1 dated May 9, 2006,” (January 2, 2006)
(incorporated by reference, see Sec. 73.8000). Although not incorporated by
reference, licensees may also consult ATSC A/54A: “Recommended Practice:
Guide to Use of the ATSC Digital Television Standard, including Corrigendum
No. 1,” (December 4, 2003, Corrigendum No. 1 dated December 20, 2006, and
ATSC A/69: “Recommended Practice PSIP Implementation Guidelines for
Broadcasters,” (June 25, 2002) (Secs. 4, 5, 303, 48 Stat., as amended, 1066,
1068, 1082 (47 U.S.C. 154, 155, 303)). ATSC A/54A and ATSC A/69 are
available from Advanced Television Systems Committee (ATSC), 1750 K Street,
NW., Suite 1200, Washington, DC 20006, or at the ATSC Web site:
http://www.atsc.org/standards.html .


73.682 in it's entirety here :

http://www.hallikainen.com/FccRules/2008/73/682/

See this post (http://www.avsforum.com/avs-vb/showthread.php?p=12803944#post12803944) a bit further down in that thread.

Oh good grief. IMHO, mandated chaos by our government is just plain wrong, if not stupid. Then again, I expect nothing less out of our government.

Yes, there will be those that think it is a good thing, but to mandate it?

I understand that even if it wasn't mandated, the odds of a station willing to spend the money to rebrand will be slim, considering all of the money spent just going digital. So, the stations themselves would be contributing to the chaos.

Those of us here on the forum fully understand that A != B in most situation and know how to find out what is what. But to Joe and Jane average consumer, I can just hear the complaints bout not being able to get channel X.

It is going to be interesting. :D

Before FCC required VCT major Channel # = analog channel # (Which BTW didn't happen until 2005), we had some stations voluntarily following ATSC A65 Guidelines and doing it that way and some stations not and either not sending PSIP at all(which some receivers had problems with), or using RF digital Channel # as the Major channel # in VCT. That was even MORE confusing IMO.

Having VCT Major channel # = Analog channel # is fine, and most would probably agree even desireable from the "channel surfing" perspective, and from the "stations wanting to keep their existing channel branding perspective" .....

But it seems to me, from everything I've seen regarding this issue, they didn't seem to put much thought (or care, perhaps) into the perspective of the OTA user setting up their reception when an "autoscan" doesn't find everything that's there when it's the case the user does not know anything other than the "virtual channel #", and in some cases does not have a receiver which will even allow them to manually input a RF channel # and adjust antenna for best results while looking at some sort of signal quality meter/etc ....

But it seems to me, from everything I've seen regarding this issue, they didn't seem to put much thought (or care, perhaps) into the perspective of the OTA user setting up their reception when an "autoscan" doesn't find everything that's there when it's the case the user does not know anything other than the "virtual channel #", and in some cases does not have a receiver which will even allow them to manually input a RF channel # and adjust antenna for best results while looking at some sort of signal quality meter/etc ....

Bingo. Matches what I've also written.

If they would have written into this whole mess where every station in an area listed every other station, then a scan would only need to find one station, as it would list all of the others in the receivable area. Too late to do that now, as current receivers probably wouldn't know what to do with multiple TSID/VCT values. Just like the authors of this mess failed to build in emergency data streams, which means we'll end up with the same crap of stations overlaying the screen with weather warnings/watches. The emergency data stream could have been used for so much more.

All too late to do anything about.

All too late to do anything about.

The rules could be changed at any time such that :

Major Channel Number in VCT must = RF channel #.

It probably won't happen, though ...

It probably won't happen, though ...

True. But I was referring to technical issues that can't be done now.

I don't think they're even thinking about it.

Last I heard, ATSC is working on upcoming Mobile TV (ATSC M/H) and ATSC 2.0 standards ... Which will of course be backwards compatible, meaning the current receivers will still "work" like they do now, but won't be able to utilize the new services ...

... and ATSC 2.0 standards ...

Heard any scuttlebutt as to what those might be?

Heard any scuttlebutt as to what those might be?

Here's a thread with some info :

http://www.avsforum.com/avs-vb/showthread.php?t=1029236

Here's a thread with some info :

Ya, I knew about the Mobile DTV thing, I was wondering if there was something else coming down the pipe. Guess not.

Mobile DTV does nothing for me in my home, which is firmly attached to the ground :D

Well, I'd originally replied with a bit more info but it was lost along with all the other 8/2~8/11 posts (**it happens) ...

For instance, I think there is a bit of info in one of the tvtechnology articles(or one I didn't post URL to from tvtechnology) I posted link to in that mobile DTV thread about ATSC 2.0 as well (deals with non-"real time" downloadable content/etc) ...

Update: Too lazy to dig that one up currently Here's a couple of (older) articles that mention a bit about ATSC 2.0 and the other "enhancements" (mobile DTV via M/H/etc) ATSC is working on :

http://broadcastengineering.com/RF/atsc-enhancements/

http://www.tvtechnology.com/pages/s.0064/t.5778.html

A short quote about ATSC 2.0 From the Broadcast Engineering article at above linke :

"The ATSC Planning Committee is also in the process of developing requirements for ATSC 2.0, which is envisioned as a complete suite of next-generation services for the conventional fixed DTV receiver viewing environment. ATSC 2.0 might include interactive services (ACAP), NRT and enhancements for fixed indoor reception, such as new codecs. All services, however, are planned to have backward compatibility with current ATSC receivers."

----------------

Oh ... Also to attempt to also answer someone else's post which was also "lost", but that I didn't get a chance to reply to earlier .... "backwards Compatiability" in this context really mostly just means the new services won't "crash" the "current ATSC receivers", it doesn't mean they can actually implement the new services (if/where/when they are implemented by the broadcaster) .... you can't for example decode AVC/H.264 streams with a MPEG2 only hardware decoder, nor will M/H streams make reception any "better" with current receivers of the current (or future) fixed services .....

---------

I DON'T UNDERSTAND WHY THE DIGITAL TV STATIONS THAT HAS OR WILL CHANGE TO A NEW CHANNEL DO NOT GIVE THEIR TRUE CHANNEL WHEN THEY GIVE STATION ID ? WHY DOES THE DIGITAL TV TUNER SHOW, FOR LIKE WMAR-TV HD CH 52 SHOWS AS 2.1 AND NOT SHOW THE TRUE CHANNEL 52. WHY DOES THEY WANT TO FOOL THE PUBLIC ? WITH SO MANY STATIONS MAYBE CHANGING TO NEW CHANNELS NEXT YEAR, WHATS GOING TO HAPPENED? SOME STATIONS WILL BE CHANGING BACK TO THEIR ANALOG CHANNEL AS DIGITIAL NEXT YEAR.

TOM YINGLING
ka3tcc@verizon.net

^ It was done that way so stations can keep their exisitng channel branding and so viewers can channel surf to the channel #'s they're used to with analog regardless of where on the dial the station is actually transmitting.

Of course, for stations moving to their analog channel post-transition, The RF channel # and VCT(virtual channel table) major channel # will be the same #.

TOM YINGLING

Please, no shouting. Turn off that caps-lock.

As indicated in the above posting, it is so that they can keep their branding.

Bottom line. No one wanted to spend the money to retool. It all came down to the almighty $$$. Now we'll be stuck with some people trying to tune to the channel directly and getting nothing. In some cases, it is going to be a nightmare. Not one station in my market is returning to their analog channel. All will be on different physical channels.

Bottom line. No one wanted to spend the money to retool. It all came down to the almighty $$$. Now we'll be stuck with some people trying to tune to the channel directly and getting nothing. In some cases, it is going to be a nightmare. Not one station in my market is returning to their analog channel. All will be on different physical channels.

Yep. Here in the Austin market, the only digital broadcaster which will actually be using its historical channel number will be channel 7 (which is moving its digital RF channel 56 back to 7 in February). All the others are keeping the digital RF channels they are using today.

If a tuner can detect the virtual mapping correctly (i.e. entering "24" and having the tuner correctly locate our local ABC affiliate's channel 24-1 on RF channel 33), the confusion will be reduced -- but probably not eliminated.

If a tuner can detect the virtual mapping correctly (i.e. entering "24" and having the tuner correctly locate our local ABC affiliate's channel 24-1 on RF channel 33), the confusion will be reduced -- but probably not eliminated.Unless the tuner has previously tried to pull in RF33 and seen in its PSIP stream that its virtual major channel number is 24, how would it know where to look to tune in virtual channel 24?

Unless the tuner has previously tried to pull in RF33 and seen in its PSIP stream that its virtual major channel number is 24, how would it know where to look to tune in virtual channel 24?
Some tuners can be instructed to "scan" all RF channels from 2 to 69 and get the PSIP information for signals it can pick up. My DTT-901 can do that, for example. And when you do that scan of all channels, even if you never tuned to it other than that, if you enter "24" it knows to go to RF 33 because it has already seen in the scan that RF 33 maps to virtual 24-1.

If you don't do that scan ahead of time, you're right -- the tuner won't know '24' means to go to RF 33 until it has already "seen" that RF 33 maps to it. At least that's how I understand it.

Why would anone want to have to memorize new channel #'s; that's stupid. if for instance FOX13 here has always been known as channel 13, OR cw44 has always been known as channel 44, WEDU Channel 3 has always been known as channel 3, or WFLA Channel 8 has always been known as channel 8 why would anyone want to start having to refer to them as anything else?? In most areas stations have been known by their channels for 40-60 years so why confuse it all. If channels weren't remapped, channel 13 would be channel 12, channel 44 would be channel 59, channel 3 would be channel 13 and channel 8 would be channel 7, etc etc. it was confusing enough around here in 1995 when 4 stations changed networks; at least if the digital tv system remaps stations to their traditional channel numbers that eases the confusion. if the set top box or TV tuner or whatever does the work for you why does anyone care about the remapping? Most people will not give a diddly what REAL channel these stations are on.

I'm pretty sure all this has been covered earlier in thread, so apologize for any repetition, but in case it helps to say some of it in a different way, perhaps :


Some tuners can be instructed to "scan" all RF channels from 2 to 69 and get the PSIP information for signals it can pick up.


In fact I don't know of any DTV receiver that doesn't have such an autoscan function, other than if your receiver is a ATSC capture card or USB "stick" used with a PC and certian software is used ...

However, the problem is, In many cases, certian signals which are receivable(*could be* picked up) but PSIP(or audio/video or anything else in the transport stream) can't be decoded during a autoscan without an adjustment of receive antenna.

Some receivers allow for subsequent scans (called "EZ-ADD" on Zenith DTT900/901) which allow for different aiming of antenna without "wiping out" the channel info stored from other stations found on original scan. This is helpful if you are using say, an outdoor directional receive antenna and know precisely how antenna needs to be aimed for say a station or group of stations in a different direction --- But, is not very useful if you are attempting to blindly adjust a simple indoor antenna for best results from certian stations and expecting a subsequent "ez-ADD" to find them.

Fortunetly, some(hopefully many) receivers allow for manual channel additions(including for example Zenith DTT900/901), allowing viewer to "punch in" the RF channel number and adjust antenna for best results(or more precisely good enough results to decode PSIP from any given station/achieve a lock/scan in/save the individual station's channel info from VCT as well as TSID) while looking at a signal meter.

I believe #1). all receivers need to implement manual tuning function and some sort of "signal quality meter" as well as #2). explain it properly in the user manual, and #3). There will be many cases when OTA viewers will need to understand this issue vs. "WYSIWYG" for analog(tune to channel # you are "used to" and adjust antenna for best results on screen) and will need to know the RF channel # for stations in their area not found via autoscan, that is if they're going to be watching those stations or care whether they can get them or not .......

Unfortunetly, as we know #1 is not the case currently as we know some receivers don't allow manual tuning/individual channel scans(or have a signal meter). So far I've personally yet to see #2 occur with any user manual for DTV receiver I've seen so far .... As for #3, all I can say is, when possible I've done my best to help folks out regarding this issue, and that's probably about all I can do or say at this point that's likely to be of any use ....

Anyway, If we "pretend" we weren't using PSIP, or if VCT Major Channel Number were required to = RF channel #, I believe #1~3 above still applies, and there would be issue of OTA viewers needing to learn the new channel #'s, including for channel surfing ... And, in that case if stations rebranded to the new RF channel #, OTA viewers might not see the rebranding in many(or most?) cases until after they acheive reception .... That may be less confusing and easier to deal with than explaining to viewers who can't find everything via autoscan how "virtual channel mapping works", though, I don't know ....

Unless the tuner has previously tried to pull in RF33 and seen in its PSIP stream that its virtual major channel number is 24, how would it know where to look to tune in virtual channel 24?

Some tuners can be instructed to "scan" all RF channels from 2 to 69 and get the PSIP information for signals it can pick up.All ATSC tuners can do that, I should hope.  Checking a given physical channel during such a scan is an attempt to receive that channel and, if it is received successfully, to read its PSIP stream to learn the corresponding virtual major channel number, so finding it during a scan counts as an example of what I was saying: if the tuner received that channel during a scan, then it has previously received that channel.

All ATSC tuners can do that, I should hope.
The OTA component of a DirecTV HR20 doesn't -- and I assume the AM21 is the same. There is no option to scan -- you're limited to what the software thinks you might be able to get based on the location you input.

Unlike Over-the-air Only DTV receivers, E* and D* receivers can use EPG guide info from the satellite for the virtual channel info for the "locals" rather than each stations' transmitted TSID and PSIP(VCT) info. I don't know which specific E*/D* receivers may or may not actually use EPG via sat vs. PSIP data from stations.

Sorry for double post, but thought this might be of some interest regarding recent discussion.

Earlier this year I ran this poll on AVSforum :

Poll For OTA DTV/HDTV Users - Do autoscans find all your local stations? (http://www.avsforum.com/avs-vb/showthread.php?t=1017693&highlight=autoscan)

28.95% of respondants chose the option "Autoscans DON'T find all receivable stations, I must manually input some channel info." .....

I had hoped to get more responses, and I did let the poll run for 90 days, but I don't think many saw the thread after it scrolled off of first page.

Unlike Over-the-air Only DTV receivers, E* and D* receivers can use EPG guide info from the satellite for the virtual channel info for the "locals" rather than each stations' transmitted TSID and PSIP(VCT) info. I don't know which specific E*/D* receivers may or may not actually use EPG via sat vs. PSIP data from stations.

Um, you should know that zero PSIP info is transferred from the OTA ATSC station to D* or E*, as they do not transmit ATSC streams. So, they MUST use their own electronic program technology. Nothing says that can't pull PSIP programming info and place in the data stream of the feed from the area back to D*/E* and then insert it into their programming guide.

Um, you should know that zero PSIP info is transferred from the OTA ATSC station to D* or E*, as they do not transmit ATSC streams.


Actually, All "OTA ATSC stations" send MPEG2 Transport stream which isn't much different from any other MPEG2 transport stream. Among other things I demux ATSC compliant MPEG2 transport streams all the time captured from OTA ATSC stations with tools that will "work" with any(more or less) MPEG2 TS. Elementary MPEG2 Video/AC3 audio streams, PSIP and many other sorts of data can be and are transmitted within MPEG2 Transport stream by OTA ATSC stations. Also, in fact, D* or E* often do receive the "local" DTV signals(including the PSIP data) they carry OTA at a local receive point in each market before they are (eventually at some point) uplinked to satellite and before any reencoding (such as reencoding HD video using AVC for better efficiency), but AFAIK they do not currently uplink or utilize any of the PSIP data.

However, I'm sorry if I was not clear enough, but your comments, nor the info in above paragraph have little or nothing to do with what I was talking about. Perhaps I erred in not specifying I was referring specifically to functions performed by/involving the OTA DTV (ATSC) receivers "contained within many D* and E* HD receivers, so to clarify :

What I was reffering to is that E* and D* receivers that also receive OTA DTV *could*(as in potentially can) receive and utilize PSIP info as received OTA by the users receiver from the stations and use that rather than, or in addition to EPG info received from the satellite(which includes the virtual channel info for each station, but no it's not transmitted by E* and D* EPG as a PSIP stream). And, I was stating I do not know which ones (if any) of those D*/E*+OTA receivers do or do Not utilize any of the PSIP data as received by the user's D* or E* receiver, OTA.

I do know at one time, certian E* and D* receivers with OTA DTV(HD) reception capability only utilized the EPG info from the satellite, including for the virtual channel info for the stations in the subscribers market(or nearby market/etc per the "zip code" they punched in for their location) which the subscriber received OTA with his E*/D* HD receiver. I also know in one case involving E* receiver/firmware, how it worked to "coordinate" the signal received OTA with the EPG info(and virtual channel info) sent from the satellite was that the receiver "matched up" the TSID as received via the terrestrial OTA/ATSC signal by the receiver to TSID info sent for that station via the EPG from the sat.

BTW, TSID(transport ID) is specific to MPEG2 transport streams(and each ATSC OTA station transmits a unique ID), is in the TS's PAT (program association table) and is also pressent in PSIP VCT(virtual channel table).

Here is a TSID lookup site which will tell you the TSID for any given ATSC station :

http://www.etherguidesystems.com/tools/tsidlookup.aspx

Actually, All "OTA ATSC stations" send MPEG2 Transport stream which isn't much different from any other MPEG2 transport stream. Among other things I demux ATSC compliant MPEG2 transport streams all the time captured from OTA ATSC stations with tools that will "work" with any(more or less) MPEG2 TS. Elementary MPEG2 Video/AC3 audio streams, PSIP and many other sorts of data can be and are transmitted within MPEG2 Transport stream by OTA ATSC stations. Also, in fact, D* or E* often do receive the "local" DTV signals(including the PSIP data) they carry OTA at a local receive point in each market before they are (eventually at some point) uplinked to satellite and before any reencoding (such as reencoding HD video using AVC for better efficiency), but AFAIK they do not currently uplink or utilize any of the PSIP data.

Go back and look again at an ATSC stream with TSReader. Hopefully that is the program you use.

PSIP data is NOT, I repeat NOT, embedded in the MPEG-2 video stream. The PSIP data stream is its own stream within the ATSC mux. The ATSC definition of the mux has workings that is very similiar to DVB. What makes is ATSC, IMHO, is the PSIP stream and what it is defined to contain. You throw away the PSIP data stream and all you really have is what looks just like DVB-S, if you throw away any PIDs that are data streams (which carry timecode, those program datamarkers, etc. Basically the VBI is placed into the separate datastream, which the matching receiver will place back into the video.)

So, video, audio and PSIP data are all separately placed into the "mux" that is broadcast via the 8VSB (also incorrectly named) OTA carriers.

Since I don't get D* or E*, I can't look to see if any of the PSIP data is sent back to the D*/E* head ends. But, I believe you are correct in that none if it is decoded at the location in which the channel is received and then shipped to the headends. Hell, D* can't even get the closed captioning right. On Monday nights I eat at a particular place and tune one of the TVs to the local channel for the news. That TV is on the DTV receiver. 9 times out of 10, the CC isn't working. When the TV was on cable and tuning the analog channel, the CC was there all the time. If they can't get that simple thing to work, getting PSIP decoded and shipped correctly to the headend would probably be a nightmare :D

BTW, part of the confusion might be in your calling it a MPEG-2 transport stream. A transport stream is a transport stream. The video could be H.264 (funny that, since I have transport stream files with H.264), MPEG-2 or even... MPEG-1. The transport stream could be nothing but 20 audio streams, and no video. In this case, the ATSC standard defined transport stream has MPEG-2 video. I'd much prefer that it had H.264, but it doesn't.

We might be squabbling over the same thing, just using the terms a little differently.

However, I'm sorry if I was not clear enough, but your comments, nor the info in above paragraph have little or nothing to do with what I was talking about. Perhaps I erred in not specifying I was referring specifically to functions performed by/involving the OTA DTV (ATSC) receivers "contained within many D* and E* HD receivers, so to clarify

Ah, OK, I thought you were talking about tuning in the local channel as fed by the local-into-local onto a D*/E* sat channel.

BTW, TSID(transport ID) is specific to MPEG2 transport streams(and each ATSC OTA station transmits a unique ID), is in the TS's PAT (program association table) and is also pressent in PSIP VCT(virtual channel table).

I believe that is incorrect to call it a MPEG-2 transport stream, as mentioned above.

Here is a TSID lookup site which will tell you the TSID for any given ATSC station :

http://www.etherguidesystems.com/tools/tsidlookup.aspx

Actually, you give it a TSID value and they tell you who it is assigned to. Even then they don't give the call letters, just the channel numbers and the location. I saw no way to input a call sign and get back that station's TSID.

They even call it a MPEG-2 transposrt stream. The video could easily have been MPEG-4. Doesn't make the whole ATSC standard any different, in that it would still be the same mux, but just containing MPEG-4 video instead of MPEG-2.

I guess we are just getting lazy on what we call things. I must be too fussy. :cool:

Here's one for ya... what to you call a transport stream that contains 4 H.264 video streams and one MPEG-2 video stream? Extra points if you know what I am talking about.;)

Hey, this kinda reminds me of earlier days on AVSforum ... I expect we might be boring most everyone else reading this thread, though, and this sort of thing does tend to cut down on needed sleep ...

but what the heck ...


Go back and look again at an ATSC stream with TSReader. Hopefully that is the program you use.


TSreader is one(excellent) tool I use quite often ...

From TSReader website http://www.coolstf.com/tsreader/index.html :


Introduction

TSReader is a transport stream analyzer, decoder, recorder and stream manipulator for MPEG-2 systems. It supports DVB, ATSC and Digicipher® II extensions to the base MPEG-2 specification. TSReader gives the user the "big picture" overview of what's being carried inside MPEG-2 transport streams and can be very useful for finding errors or inefficiencies. If you're not familiar with MPEG-2 transport streams , we suggest reading our web page about North American MPEG-2 Information as this covers this subject in depth.





PSIP data is NOT, I repeat NOT, embedded in the MPEG-2 video stream.


Of course not, I didn't say it was.

The PSIP streams/tables are muxed with MPEG2 Video and AC-3 audio streams, and MPEG2 PSI info such as is contained in PAT/PMT's, and anything else they might be sending - datacast streams, Null packet stream/etc, h.264 video streams such as when USDTV were using those, whatever --- into a ATSC compliant MPEG2 Transport stream, or "ATSC mux" if that's what you want to call it. Note You'll also find seperate streams for the EIT's (PSIP Event information tables - detailed program info can be here).


The PSIP data stream is its own stream within the ATSC mux.


Call it "ATSC Mux" or MPEG2 Transport stream, either way the PSIP tables and data Streams(plural) just as I said are all encapsulated within it, just as any other stream(including MPEG2 video/AC3 audio streams) contained within the TS, just like I said in my previous message.


The ATSC definition of the mux has workings that is very similiar to DVB.


That's mostly because both use MPEG2 Transport Streams.

Really recommend/suggest you download and study the various ATSC documents, especially the A/53 and A/65 documents.

Here are a couple of links to get you started :

http://www.atsc.org/standards.html

http://www.atsc.org/standards/a53.html


any PIDs that are data streams ....


PIDs are packet identifers not "data streams" ..... I would define them as idenfiying which elementary stream a packet "belongs to", but Here's ATSC's current "offical" definition from one of the ATSC A 53 documents :

packet identifier (PID) – A unique integer value used to associate elementary streams of a
program in a single or multi-program transport stream.

TSreader simply lists streams (such as in the "tree List" or bandwidth charts/pid lists) by the PID's "associated" with them .....



So, video, audio and PSIP data are all separately placed into the "mux" that is broadcast via the 8VSB (also incorrectly named) OTA carriers.


They(and any other streams sent within the TS - Datacast streams for instance) are seperate streams with unique PID's(packet Identifiers). for each stream.

8VSB is just another, shorter abbreviation of 8T-VSB. Either abbreviation refers to the signal modulation used for Over the air ATSC DTV, which is (unabbreviated) : Trellis-coded 8-level vestigal sideband.

There's a pretty good explanation of 8VSB(8T-VSB if you like) in ATSC docs, and here :

http://www.broadcast.net/~sbe1/8vsb/8vsb.htm

16VSB is also "spec'd" in ATSC standards, but does not use the trellis coding (and can be used for digital cable applications, but isn't used in U.S. for digital cable, instead QAM256 is used), but is probably not widely known (or widely used, if it is used at all for any real world application), which I would guess is probably why we more commonly see the 8VSB abbreviation used rather than 8T-VSB ....


Hell, D* can't even get the closed captioning right.


Along those lines, It has gotten better, but I've noticed many broadcasters seem to have some "issues" implementing the EIA-708 (digital) captions, either at all, or properly ... Note: BTW, EIA-708 captions are implemented as User data that is data which is contained within elementary MPEG2 Video stream ... So is AFD data (although there is also AFD descriptor, I can't remember where it "goes", If I recall correctly without digging it up, I think it goes in PMT and/or VCT ...)



A transport stream is a transport stream.


No. From ATSC A53 part 1 Part 3 – Service Multiplex and Transport Subsystem
Characteristics (A/53, Part 3:2007), section 6.1 :


6.1 MPEG-2 Systems Standard
The transport subsystem shall comply with the transport stream definition of the MPEG-2 Systems standard as specified in ISO/IEC 13818-1 [3] and shall be further constrained as specified herein.


As for PSIP within the TS :


6.6 Services and Features
6.6.1 System Information and Program Guide Transport Streams shall include system information and program guide data formatted according to the structure and syntax described in ATSC Standard A/65 “Program and System Information Protocol for Terrestrial Broadcast and Cable” [2] ....System information and program guide data shall be conveyed in Transport Stream packets of PID 0x1FFB, which shall be reserved exclusively for this purpose. System information provides data necessary for navigation among
digital service offerings. The program guide database allows a receiver to build an on-screen grid of program information for the various services that may be available.

6.6.1.1 SI base_PID for TS-M
System information and program guide data shall be conveyed in Transport Stream packets of PID 0x1FFB, which shall be reserved exclusively within TS-R (Figure 9.2) for this purpose.
6.6.1.2 SI base_PID for TS-E
System information and program guide data shall be conveyed in TS-E packets of PID 0x1FF9, which shall be reserved exclusively within TS-R (Figure 9.2) for this purpose.
6.6.1.3 System Information and Program Guide STD Model The STD model for program guide and system information is specified in ATSC Standard A/65



Way too much info in this document to include much of it here, so I'm sure you'll want to utilize the entire document, available here :

http://www.atsc.org/standards/a_53-Part-3-2007.pdf

I also have a more detailed document describing MPEG2 Transport streams and how they work in great detail -- I think I'd gotten that off ATSC site as well several years ago, but can't dig it up now (I know I have it archived on a DVDR or CDR somewhere, but it's getting too late for me to dig it up at present) ..

Oh, BTW, the a53 "guide to DTV standard" document is split up into various parts, other sections of it which delve into other aspects of ATSC "DTV standard" (such as signal modulation - 8VSB(or 8T-VSB if you like) and 16VSB included) can also be downloaded from ATSC site as well as more detailed info on each "specific" ATSC standard (a65/PSIP for instance) ...


The video could be H.264


Yes. As just one reference I quickly dug up for MPEG-4, which would include H.264 video(MPEG-4 AVC/x.264/etc),
From a document from "INTERNATIONAL ORGANISATION FOR STANDARDISATIONORGANISATION INTERNATIONALE DE NORMALISATION ISO/IEC JTC1/SC29/WG11 CODING OF MOVING PICTURES AND AUDIO" available here :

http://www.chiariglione.org/MPEG/STANDARDS/MPEG-4/MPEG-4.HTM


In principle, MPEG-4 does not define transport layers. In a number of cases, adaptation to a specific existing transport layer has been defined:

Transport over MPEG-2 Transport Stream (this is an amendment to MPEG-2 Systems)
Transport over IP (In cooperation with IETF, the Internet Engineering Task Force)




Here's one for ya... what to you call a transport stream that contains 4 H.264 video streams and one MPEG-2 video stream?


If it's ISO/IEC 13818-1 [3] compliant I'd probably call it a MPEG2 Transport Stream ;) ....


Actually, you give it a TSID value and they tell you who it is assigned to. Even then they don't give the call letters, just the channel numbers and the location. I saw no way to input a call sign and get back that station's TSID.


Yeah, you got me there ... It is the best thing for "TSID lookup" I've ran across so far however, as I haven't found any list/spreadsheet database with the station info*(callsign)+TSID info included ...

It's come in handy for me, especially on one occasion when (verified via TSreader) one local station was sending incorrect TSID (they were sending the analog station's TSID on the digitial - Yes, analog stations have been assigned TSID's as well), This caused problems with EPG for Some E* receivers and new firmware at the time which as I described before was using the "correct" TSID info, which didn't "match" with the incorrect TSID info received via the TS from the station, OTA ... A quick note to the station's engineers and they got on it fairly quickly .....


They even call it a MPEG-2 transposrt stream.


They, me and up until now, every thing I've ever read about them or anyone else I've ever talked to about them ;)

Thanks for the info... now how can I use the information TVFool gave me to determine the strength of the antenna I will need?

now how can I use the information TVFool gave me to determine the strength of the antenna I will need?

Sorry noone has responded to this, given it's been a month since you asked ... Assume you've probably already figured it out by now, but if not, and if you haven't already read it, be sure to read the TVfool Signal Analysis FAQ:

http://www.tvfool.com/index.php?option=com_content&task=view&id=14&Itemid=50

The info there on how to interpet the plot should give you a good idea of what sort of antenna you need --- But, if you want more specific information/advice, please post your TVfool plot --- usually best to do that in your local thread as local folks are usually more familiar with certian specifics regarding stations and reception in area -- But if you wish, feel free to post it here and we'll be glad to try to help as well ...

The reason I ask is because when I hit display on my TV they say analog. I have two TV’s (1 is a year old. the other just got) one is on regular cable (no box) and the other is digital (after buying the extra box) according to the cable provider. But both say analog on the display. I can not see any difference in the reception.

Bill,
You are a cable customer. No OTA reception is involved, so this is the wrong thread.

That said, your TVs say "analog" because:
- the older set is (analog) "cable ready" so it can tune the analog signal from the cable.
- the newer set is on a cable box, the box is decoding a digital signal to analog and sending it to the TV.

You can tell usually by the channel range; my older cable-ready set only tunes channels2-99. The digital box accesses channels 100-1000+.

If you want your new TV to receive a digital signal, get a cable box with a digital output that's compatible with your TV. Assuming the TV accepts HDMI, the box should have either an HDMI or DVI output, and you'll use an HDMI cable, or an HDMI-to-DVI cable respectively.

FWIW, I can't see any difference between component and HDMI connections, but then I have a very forgiving TV.

HAve fun,
Frank

Thanks for the infomation. I looked at both TV's and the cable box. The TV's have hook up for HDMI. The box does not. I guess I should ask for a new box.

BILL

OK here goes.:D
I have plans for a homemade antenna. Similar to this:
http://www.youtube.com/watch?v=EWQhlmJTMzw

Instead of coat hangers how is 12 gauge copper? Is it "better" for reception?

Hope this is the right place for this.

Kelly

OK here goes.:D
I have plans for a homemade antenna. Similar to this:
http://www.youtube.com/watch?v=EWQhlmJTMzw

Instead of coat hangers how is 12 gauge copper? Is it "better" for reception?

Hope this is the right place for this.

KellyI have made many of these antennas, some with 14 gauge copper & most with coat hangers or aluminum 12 gauge copper.
This forum has a How to build a UHF antenna. It has 33 pages of good stuff. Here is the link.
http://www.avsforum.com/avs-vb/showthread.php?t=798265

Hi Everyone,

I have been reading about all the great OTA solutions that you have given. I have a real problem about our CBS affiliate WHBF in Rock Island, IL. After transition it will go back to RF-4 with 24kw of power. I live 47 miles from the transmitter in Davenport, IA. Presently all my OTA is UHF, analog on RF-4, 6, 8, and 12. I get good reception on all analog channels but my power lines are in a directly in front of reception from the QCA, thereby giving me heavy electrical interference on the low band VHF channels. I want to know if there is a solution to removing the electrical interference. I also have powerful FM transmitters (50 kw each) a mile and a half from me and an analog TBN affiliate on RF-51. i wish satellite and cable were an option, but they are not. My OTA UHF setup is a CM 4221 with a Radio Shack amplifer at 30' AGL. My analog VHF is 15' above ground with no amplification. Do you think there is any way of getting WHBF after conversion reliably, or should I give up and use WMBD-CBS (RF 30) out of Peoria. I would like to get RTN that WHBF will carry if possible.

Thanks

Good ideas, spokybob

I want to know if there is a solution to removing the electrical interference.

Call the power company. If the interference is created in their lines they are required to fix it. The FCC fined a power company in California $10,000 because they wouldn't fix interference.

To track the source, tune your car radio to an unused frequency near the low end of the dial. (540-590) Drive down the street listening for a loud buzz. The loudest buzz will be close to the source of the problem. This trick works much better during the daylight hours when there is no skip.

Yes, Canada has been adopting the same ATSC (8VSB) digital OTA standard as in the U.S.A. so there are Digital OTA stations in the four largest cities, with more cities and stations to come and many more available from U.S. border zone cities. Analog NTSC stations have overlapped the border from both sides for over 5 decades.

Canada has set its date for full digital conversion to August 31, 2011.

The frequency spectrum of Canadian TV (VHF-LO, VHF-HI, UHF) is identical to that of the U.S.A., so Canadian OTA antennas and equipment are therefore exactly the same. UHF Channels 52 through 69 are to be eliminated in the future for reassignment to other purposes. There is debate in Canada about reassignment (if/whether/when) of the VHF-Low band (Channels 2 through 6) but no official policy has been decided yet.

The technical authority over OTA is the federal government department known as Industry Canada (IC), while the licensing authority over OTA stations is held by another government body known as the CRTC. Since border zones overlap each country's territory, IC and the FCC work together to administer those areas.

Accessing IC's OTA TV station database is unfortunately not an interactive, web-based ability at this time, so I run a data pump of IC's database, which I then process/massage into HTML tables for Canadian provinces & territories and U.S. border zone states:

http://www.user.dccnet.com/jonleblanc/Canada_TV_Stations/

Enjoy!

I'm a neophyte on the technical aspects of this topic, so please excuse my ignorance. I'm thinking of buying a flat panel hdtv and will use OTA for reception. My question concerns the type of hdtv that will be most appropriate for OTA, a 720p or 1080p. Does OTA provide 1080p type of signal or should I just buy a 720p hdtv? Of course there's a huge cost difference but I would like to buy a 1080p hdtv if it makes sense when combined with using OTA reception. If not, I'll get a 720p set. Thanks.

I'm a neophyte on the technical aspects of this topic, so please excuse my ignorance. I'm thinking of buying a flat panel hdtv and will use OTA for reception. My question concerns the type of hdtv that will be most appropriate for OTA, a 720p or 1080p. Does OTA provide 1080p type of signal or should I just buy a 720p hdtv? Of course there's a huge cost difference but I would like to buy a 1080p hdtv if it makes sense when combined with using OTA reception. If not, I'll get a 720p set. Thanks.

IMHO you want a 1080p set that will do 1080/24p. While OTA stations are only 720/59.94p (Fox/ABC) and 1080/59.94i (CBS/NBC/CW), you will eventually purchase a Blu-ray player that will handle 1080/24p and you'll want a display that will work with it.

Blu-ray players will work with 720p displays, but for the BEST viewing pleasure, a 1080p set is the best. Yes, it will cost more in the end, but you won't kick yourself in the butt later an.

So, from what I'm reading here, VHF Low Band is still in use for DTV. :confused:

If that is the case, I'm very happy! :)

More E-SKIP and F-SKIP with positive ID. I can't wait! ;)

Sorry noone has responded to this, given it's been a month since you asked ... Assume you've probably already figured it out by now, but if not, and if you haven't already read it, be sure to read the TVfool Signal Analysis FAQ:

The info there on how to interpet the plot should give you a good idea of what sort of antenna you need --- But, if you want more specific information/advice, please post your TVfool plot --- usually best to do that in your local thread as local folks are usually more familiar with certian specifics regarding stations and reception in area -- But if you wish, feel free to post it here and we'll be glad to try to help as well ...

I live near LAX, 23 miles from the TV transmitters on Mt. Wilson. My rooftop antenna (a brand new Radio Shack VU-90 XR) is pointing directly at the transmitters, with no blockage. I use about 40' of coax to connect to my Toshiba 52RV53U TV. While the analog versions of local stations look fine, I can't get any of the digital versions (5.2, 2.1, 4.1, 11.1, etc.). I get a message that signal level is too low. Any suggestions?

Thanks.

... I can't get any of the digital versions (5.2, 2.1, 4.1, 11.1, etc.). I get a message that signal level is too low.

* Have you set the TV for Antenna input, as opposed to Cable/Satellite? The selection is located in the Terrestrial sub-menu of the Installation menu. Re-scan the channels if you need to do this.

If that's all set, basic troubleshooting is in order:

* Is the antenna aimed correctly? The "open" end of the antenna should face the signals. Pointing the antenna in the opposite direction is a common error.

* Is the antenna mounted on a mast so that it is level with the ground?

* Check the antenna carefully, making sure that the two phasing lines -- cris-crossing, bare aluminum wires parallel to and above the boom -- aren't touching each other anywhere. They can be separated by bending the wires slowly and carefully if need be.

* Is the Toshiba the only TV connected to the antenna, and if so, are you using an amplifier? DTV signals are much easier to over-amplify than analog broadcasts; too much amplification equals no reception. No amp should be necessary at that distance with a roof-mounted VU-90 connected to a single TV.

* The VU-90 is new, but what about the coax cable? Was that replaced at the same time? Old cable can be corroded, which will have an impact on digital reception as well.

* If it's new cable with factory connectors, it may be defective or damaged. Replacement may be in order.

* Did you make up the cable connectors yourself? Double-check all connections to be sure a small strand of the outer shield isn't touching the center conductor somewhere, creating a short.

* Swap out the matching transformer up at the antenna for a new one. Also known as a balun, the transformer couples the coax with the antenna terminals. Baluns can go bad.

* Have you set the TV for Antenna input, as opposed to Cable/Satellite? The selection is located in the Terrestrial sub-menu of the Installation menu. Re-scan the channels if you need to do this.

If that's all set, basic troubleshooting is in order:

* Is the antenna aimed correctly? The "open" end of the antenna should face the signals. Pointing the antenna in the opposite direction is a common error.

* Is the antenna mounted on a mast so that it is level with the ground?

* Check the antenna carefully, making sure that the two phasing lines -- cris-crossing, bare aluminum wires parallel to and above the boom -- aren't touching each other anywhere. They can be separated by bending the wires slowly and carefully if need be.

* Is the Toshiba the only TV connected to the antenna, and if so, are you using an amplifier? DTV signals are much easier to over-amplify than analog broadcasts; too much amplification equals no reception. No amp should be necessary at that distance with a roof-mounted VU-90 connected to a single TV.

* The VU-90 is new, but what about the coax cable? Was that replaced at the same time? Old cable can be corroded, which will have an impact on digital reception as well.

* If it's new cable with factory connectors, it may be defective or damaged. Replacement may be in order.

* Did you make up the cable connectors yourself? Double-check all connections to be sure a small strand of the outer shield isn't touching the center conductor somewhere, creating a short.

* Swap out the matching transformer up at the antenna for a new one. Also known as a balun, the transformer couples the coax with the antenna terminals. Baluns can go bad.

Don,
Thanks for the detailed response. I called the Toshiba tech support 800# (before I saw your post). The technician was knowledgeable, and instructed me to select the antenna mode, then do another channel search. That solved my problem; I had done my initial scan in antenna/cable mode, but hadn't specifically chosen antenna. Now I get a lot of digital stations with no issues.

I have a Radio Shack rooftop mounted antenna. What kind of grounding do I need to do? The antenna itself is mounted with metal clamps to a metal vent pipe. Do I need to run another ground wire from it? Do I need to run the coax cable through some type of ground block? Can I ground a splitter for this purpose?

I have a Radio Shack rooftop mounted antenna. What kind of grounding do I need to do? The antenna itself is mounted with metal clamps to a metal vent pipe. Do I need to run another ground wire from it?

Hi again. Yes, you do: The mast and mount need to be grounded. The ground wire can be secured to any of the mount's lugs or screws. The best basic guide for putting together a proper grounding system is "Grounding outdoor antennas," located about three-quarters of the way down this page (http://www.hdtvprimer.com/ANTENNAS/basics.html).

Do I need to run the coax cable through some type of ground block?

It's a good idea to do so. This prevents static buildup in the coax shield. Ground blocks have a hole through which the grounding wire can be threaded.

Can I ground a splitter for this purpose?

If it's outdoors, sure, but doing so is redundant if the coax is connected to a ground block. Indoor splitters shouldn't be grounded to anything. The whole idea is to make sure static and lightning discharge to ground outside your home.

I'm a tad surprised the RS guy or gal didn't try to sell grounding equipment along with that new antenna...

Good to hear the original problem was a simple setting adjustment in the TV.

My friend has a High Def Tv with NTSC built in tuner but not ATSC tuner. If he were to hook up a digital convertor box would it provide him the digital reception. In addition, would it give him High Def on his tv for those digital stations broadcasting High Def??
An answer on this would be appreciated since it will determine if it is worth his while to get a convertor box.........Thanks for any help.

My friend has a High Def Tv with NTSC built in tuner but not ATSC tuner. If he were to hook up a digital convertor box would it provide him the digital reception. In addition, would it give him High Def on his tv for those digital stations broadcasting High Def??

Simple answers: YES! NO!

Long answer: The CECB boxes are only for providing DTV reception for old analog TVs and VCRs. You will need a more expensive HDTV STB that has, at a minimum, component out. At best, HDMI out. It all depends on what the monitor has for digital inputs. The three types are: component, RGB, HDMI.

You mean composite, component (RGB) and HDMI?

You mean composite, component (RGB) and HDMI.

Nope, I meant exactly what I wrote. Composite is not HD, it is 480i SD.

Component and RGB have two different connector types.

Component has the 3 separate RCA connectors: Y, Pb, Pr
RGB uses the VGA connector.

I also forgot one: DVI

The only connector my older STB doesn't have is HDMI, as it didn't exist, or was really new when this particular STB was built.

Mr. Video,
Is there such a thing as digital convertor box that is for High Def with a component out connection so it could be seen in High Def?
Thanks for the help.

Yes, for example the Samsung DTB-H260F. See the STB synopsis sticky thread for others. However, you cannot use the $40 government coupons for these.

Component has the 3 separate RCA connectors: Y, Pb, Pr
RGB uses the VGA connector

Oh, my mistake. As I recall component connectors are color coded red, green and blue. Could they have made it more confusing?

Oh, my mistake. As I recall component connectors are color coded red, green and blue. Could they have made it more confusing?

Nope, they did a great job of confusion. Not sure what other color scheme could have been used, since baseband composite NTSC video and audio uses yellow, red and white.

They could have used Yel/Blu/Red, for Y/Pb/Pr. But that would have been too easy :D

I need help :) and i know this is the right place to be:

I live 5 miles from the tower cluster in my area (zip code 13790) and I am trying to pick up stations ~50 miles South that are only about 10-15 degree different than my local towers. Can I "see thru" my local towers or will they block out the signal from the distant stations?

Local stations Nm(Db) bewteen 57-70 nad distant stations -12 to -25 per tvfool

thanks :)

ps i cant get my tvfool image to post.

I live 5 miles from the tower cluster in my area (zip code 13790) and I am trying to pick up stations ~50 miles South that are only about 10-15 degree different than my local towers. Can I "see thru" my local towers or will they block out the signal from the distant stations?

Towers do not block RF signals. As long as there is enough signal reaching your outside antenna (I doubt that an indoor will work) and the antenna has gain for that distance, then you should get something. What can block the signal are very tall hills between you and the other stations.

Thanks for the reply, now one of my closest stations is broadcast on channel 12 and 2 of my distant stations are on 11 and 13, will this close station overload channels 11 and 13? Channel 12 is analog and will be shut off sooner or later but until then will this cause a signal problem for the distant 11 and 13? zip 13790

Short answer is yes. Since it appears you have to shoot through the analog to hit the distant digitals, I'd say you're out of luck. If you were farther away and those digitals were in a different direction, you might have a prayer, depending on how much you'd want to spend on aluminum, towers and traps. I'd wait until cutoff - whenever that might be - and work on it then.

Thanks for the reply, now one of my closest stations is broadcast on channel 12 and 2 of my distant stations are on 11 and 13, will this close station overload channels 11 and 13? Channel 12 is analog and will be shut off sooner or later but until then will this cause a signal problem for the distant 11 and 13? zip 13790

DrDon pretty much hit the nail on the head. Co-channel analog/digital does work, as you will find many current situations where the analog is one channel above the digital. But, in those cases, the two channels are broadcast from the same antenna and have necessary power levels.

In your case, the co-channels are a lot weaker than the analog that is between them. Your tuner will more-than-likely not see the two digital, being overpowered by the analog channel.

If you has access to a spectrum analyzer, you'd see the nice large signal that is the analog and the very weak signals that are the digitals.

You are stuck until the cut-off date, whenever that might be.

Thanks Don for the information, I thought that was the case, I guess I will have to rescan periodically until the analog signal is no longer being broadcast. I am currently getting stations in Syracuse from my location and thought I might get a few more in the Scranton Direction.

My antenna is in my attic so I am happy iwth my results

hi
Got myself a new digital tv converter box for my tv .problem i am having is i set it up and i only get one tv station but if i turn the converter box off i get all kinds of channel like 23,26,29,17 and so on .is there something i am doing wrong.
thank you for the help.

Hi, I've had an older HDTV since this summer but I'm not currently using it to view any hd content although my pc is connected to it via component cable (vista media center).

I have a Sony KV-40XBR800 and according to the specs it doesn't have an ATSC tuner. I've been looking into finding out what equipment I would need to view OTA HD channels and how the transition is going to affect that.

Would I need to purchase a tuner AND the antenna?

Welcome to AVS. Yes, you'll need a tuner and an antenna or a tuner and cable service. You'll find a list of set-top-boxes in the STB sticky (http://www.avsforum.com/avs-vb/showthread.php?t=179095) near this thread.

As for the type of antenna you need, follow the directions in this thread and the AVS Antenna Topic. Check your local thread for help with specifics.

Once you have an ATSC tuner, about all you need to worry about post-transition is rescanning. In many cities, TV stations will flip the digital signal they're now broadcasting on another frequency back to their legacy channel or possibly even a third frequency. See the channel election thread at the top of the Local Reception forum for THOSE details.

And, if you don't mind, edit your personal details to include your rough location. Since so much of this is location specific, it helps us help you if we don't have to ask where you live.

Good luck.

hi
Got myself a new digital tv converter box for my tv .problem i am having is i set it up and i only get one tv station but if i turn the converter box off i get all kinds of channel like 23,26,29,17 and so on .is there something i am doing wrong.
thank you for the help. Are you talking about one of the converter boxes being used with a standard television?

Welcome to AVS. Yes, you'll need a tuner and an antenna or a tuner and cable service. You'll find a list of set-top-boxes in the (It won't even let me quote the URL you had because I don't have 3 posts yet :)) near this thread.

As for the type of antenna you need, follow the directions in this thread and the AVS Antenna Topic. Check your local thread for help with specifics.

Once you have an ATSC tuner, about all you need to worry about post-transition is rescanning. In many cities, TV stations will flip the digital signal they're now broadcasting on another frequency back to their legacy channel or possibly even a third frequency. See the channel election thread at the top of the Local Reception forum for THOSE details.

And, if you don't mind, edit your personal details to include your rough location. Since so much of this is location specific, it helps us help you if we don't have to ask where you live.

Good luck.

Thanks for the response. I checked the broadcast locations in my area and all of them are 15 miles or closer to where I am and behind my house off to the southeast. Luckily, in a town like this there arent really any tall structures or anything.

So if I read your response correctly, I could just get a tuner and use that in conjunction with the cable service I currently have and that'll give me my HD local channels? I guess the reason I'm confused is because of all this "digital" stuff that I have to hear everytime I turn on my tv :) I'd rather be looking at things in HD.

So if I read your response correctly, I could just get a tuner and use that in conjunction with the cable service I currently have and that'll give me my HD local channels? I guess the reason I'm confused is because of all this "digital" stuff that I have to hear everytime I turn on my tv :) I'd rather be looking at things in HD. If your cable service offers HD - and most do, I believe - call them and upgrade to the package that gets you what you want. The cable company's set top box or DVR generally costs a few bucks a month and will work with your television. Same with the satellite services.

There are tuners you can buy that'll do either ATSC (over the air) and/or what we call "clear QAM." The latter refers to the unscrambled HD stations your cable company may provide. And that's usually limited to the local broadcast affiliates and possibly a few other channels.

If you don't have or don't plan to keep your cable TV service, then you'd connect an antenna to an ATSC tuner and start scanning. Start cheap and keep receipts. Sometimes at your distance, rabbit ears will do. Other times, you may need a rooftop. Everybody's situation is different.

It all depends on the time and effort (and $$) you want to put into this.

If your cable service offers HD - and most do, I believe - call them and upgrade to the package that gets you what you want. The cable company's set top box or DVR generally costs a few bucks a month and will work with your television. Same with the satellite services.

There are tuners you can buy that'll do either ATSC (over the air) and/or what we call "clear QAM." The latter refers to the unscrambled HD stations your cable company may provide. And that's usually limited to the local broadcast affiliates and possibly a few other channels.

If you don't have or don't plan to keep your cable TV service, then you'd connect an antenna to an ATSC tuner and start scanning. Start cheap and keep receipts. Sometimes at your distance, rabbit ears will do. Other times, you may need a rooftop. Everybody's situation is different.

It all depends on the time and effort (and $$) you want to put into this.

Thanks. At this point I'm just looking to get my local channels in HD. I called Mediacom and they were trying to sell me a STB. I'm guessing thats for their base package that has the espn, tnt, tbs, etc in HD, which is fine. Its not very expensive monthly but they require a credit check first, and since I have crap credit they want me to pay $100 up front which I have no desire to do since I'm already paying $100 a month after basic cable + internet. However, if I were to get my local channels in HD for the time being and I was pleased with the quality, then I'd consider looking into it more. I just want to make sure its worth the money before I invest into it, you know?

If only two directions are of interest, it is possible to "gang" two antennas in different directions but with a 3 db loss and with the possibility of inteference.

What if you mount them each on a different mast? Say about 4 feet or so apart?

How do you connect them to the converter? What sort of "coupler" should one use?

What if you mount them each on a different mast? Say about 4 feet or so apart?

How do you connect them to the converter? What sort of "coupler" should one use? 4 feet won't make much difference if you're getting multipath or other interference. In that case, you'd be better off with an A/B switch rather than combining the antennas.

If you do go with combining, just use an ordinary splitter in reverse. Where you put the combiner (splitter in reverse) will depend on what else you put on the antenna. If you're not putting a preamp on one or both antennas, then it's not all that much of an issue.

The News Hour (PBS) did a segment tonight about the DTV transition. The expert answering the questions seemed well-informed, but then said that "digital signals are much weaker than analog" signals, and people may have trouble receiving them.

I thought signal strength would be independent of the format being delivered. Isn't the signal just as strong if the tower is sending it with the same amount of energy, or is there something about digital broadcasts that makes them weaker?

Thanks in advance for clearing up my confusion. :confused:

I thought signal strength would be independent of the format being delivered. Isn't the signal just as strong if the tower is sending it with the same amount of energy, or is there something about digital broadcasts that makes them weaker?

You'd think that, but the 8VSB modulation scheme causes the signal to "act" differetly. I'm not an RF engineer, so I can't provide you with any of the details.

But, if you could look at a spectrum analyzer display output of a digital channel and one of an analog channel, you'd see a world of difference. If you looked at the broad spectrum in your area, you'd be able to point out the digital and analog stations without any difficulties.

Technically both are analog, as you are just modulating the analog RF signal differently.

Just a reminder for anyone who stumbled across this thread (and other interested parties) wondering about HOA restrictions on what the FCC calls Over The Air Reception Devices (OTARDs) - antennas.

HOA's and their CC&Rs can not preclude installation of exterior OTA TV antennas, DTH satellite antennas, and/or MMDS wireless internet antennas (typically those flat diamond shape antennas) per FCC regulation. Note there are some FCC recognized limits to that rule. Also, the HOA can ask for installation mods or screening to minimize visual impacts, but they can not be onerous or expensive to the point where it prevents you from installing the antenna. The rule only applies to antennes with a height of less than 12 feet above the roof ridgeline. Higher than that, and things become more complicated. I'm battling an HOA where I have a rental property on this matter - their covenant on banning outdoor antennas is unenforcible. I sent them model/proposed CC&R text which complies with the FCC rule on exterior antennas, we'll see what they say. If anyone wants details, let me know.

Oh yeah, it might be helpful to include a couple of FCC links. Here they are:

www.fcc.gov/cgb/consumerfacts/consumerdish
www.fcc.gov/mb/facts/otard

Got a question and need info.
I am switching from a CM 4228 antenna to a Winegard 7698 antenna. Will this be a noticeable upgrade or am I beating a dead horse. Just trying to keep ahead of the 6/12 changeover. I also like the USA built Winegard product. I am 60 miles from south channels and 90 miles from Chicago channels and have managed to pull either direction having to bow to the reception gods on a regular basis from the north. 57 ft tower, Yaesu 800 rotor and Winegard amp. original stuff installed 8/08 and am doing some tweaking. Any antenna info appreciated.

Why not just augment the 4228 with a Winegard YA-1713? You will lose a bit of UHF gain and signal gathering ability with the 7698.

I have a Samsung plasma with ATSC and other tuners. To watch HD channels, I am planning to get an antenna. AFAIK, antennas come with a coax. Can you watch HD channels over coax? Do the HD channels not look very nice because of the cable? If you are using an antenna, is there any option other than to plug the coax coming out from the antenna into the TV? I realize I can subscribe to a HD package on satellite or cable, but I am just wondering if the quality of the picture is going to be comparable if you are catching the same channel OTA and feeding it to the tv by a coax.

I have a Samsung plasma with ATSC and other tuners. To watch HD channels, I am planning to get an antenna. AFAIK, antennas come with a coax. Can you watch HD channels over coax? Do the HD channels not look very nice because of the cable? If you are using an antenna, is there any option other than to plug the coax coming out from the antenna into the TV? I realize I can subscribe to a HD package on satellite or cable, but I am just wondering if the quality of the picture is going to be comparable if you are catching the same channel OTA and feeding it to the tv by a coax.

OTA,Satellite and Cable all use Coax Cable to carry their siginals. You will get more channel and much better HD PQ with OTA than Satellite or Cable. Most of all with OTA it FREE!

Willie

OTA,Satellite and Cable all use Coax Cable to carry their siginals. You will get more channel and much better HD PQ with OTA than Satellite or Cable. Most of all with OTA it FREE!

Willie

Thanks, that is good to know. This is a probably silly question, but let me ask it anyway. If coax can carry HD signal just fine, why are there all these different connection types - HDMI, DVI, s-vidio, component, and so on? People say that for the best PQ, use HDMI, and HDMI is better than X, and X is better than Y, etc. Is coax as good as any of these?

Why not just augment the 4228 with a Winegard YA-1713? You will lose a bit of UHF gain and signal gathering ability with the 7698.
Well that ship has sailed as I already have the 7698, just not installed yet. Please keep fingers crossed. I'm going to pray to the reception gods and hope I haven't changed what I got, I'm thinking instead of stamps I will just have a good start on a antenna collection. I will get update out when weather breaks a tad and can get up tower safely. Ice and tower climbing don't mix well. I do have an installer and we discussed stuff and he thought the 7698 would be a good move. I purchased antenna from amazon so he didn't have a big vested interest in selling etc.

Thanks, that is good to know. This is a probably silly question, but let me ask it anyway. If coax can carry HD signal just fine, why are there all these different connection types - HDMI, DVI, s-vidio, component, and so on? People say that for the best PQ, use HDMI, and HDMI is better than X, and X is better than Y, etc. Is coax as good as any of these?

Coax is for the raw signal coming from your antenna or cable provider, which contains all your channels mixed together, on different frequencies in the VHF and UHF bands.

Your TV's tuner or set-top box selects ("tunes") one of those channels and extracts the digital video and audio data from it. If the tuner is built into your TV, obviously no further external connection is necessary. If you're using a set-top box, you need to get the video and audio to your TV somehow.

HDMI is a digital connection. Component-video (red/green/blue) is analog, but with enough capacity to carry a high-definition analog video signal. S-video and composite-video (yellow) have enough capacity for only standard-definition analog. We have all these different types of connections for historical reasons. As video signals from TV etc. became better, people had to come up with better types of connections, and we keep the older types for compatibility with old TVs and video components.

Coax is for the raw signal coming from your antenna or cable provider, which contains all your channels mixed together, on different frequencies in the VHF and UHF bands.

Your TV's tuner or set-top box selects ("tunes") one of those channels and extracts the digital video and audio data from it. If the tuner is built into your TV, obviously no further external connection is necessary. If you're using a set-top box, you need to get the video and audio to your TV somehow.

HDMI is a digital connection. Component-video (red/green/blue) is analog, but with enough capacity to carry a high-definition analog video signal. S-video and composite-video (yellow) have enough capacity for only standard-definition analog. We have all these different types of connections for historical reasons. As video signals from TV etc. became better, people had to come up with better types of connections, and we keep the older types for compatibility with old TVs and video components.

Thanks for the information. I was confused because coax is rated as the worst connection type. But this is only true for a connection between a stb and the tv. It is not true for a connection between an OTA antenna and tv, or between a dish and stb. It is strange that coax can carry multiple hd channels without loss from your dish to your stb, but cannot carry one hd channel from your stb to the tv. But looks like that's the way it is. This thread also clears this up.

http://www.highdefforum.com/cables-connections/40243-coax-vs-hdmi.html

It is strange that coax can carry multiple hd channels without loss from your dish to your stb, but cannot carry one hd channel from your stb to the tv.

When you use a coax connection for analog signals, as with a VCR or the new DTV converter boxes, the box modulates the video signal onto a VHF carrier signal (channel 3 or 4) so it looks just like an OTA broadcast signal from an antenna. Then the TV has to tune it and demodulate it to extract the video, just like with a signal from an antenna. The extra modulation and demodulation steps degrade the picture.

In principle, we could use a similar setup for digital video, encoding and modulating it onto a VHF or UHF carrier signal so it looks just like a broadcast (ATSC) or cable (QAM) signal, and then your TV could receive it just like a digital broadcast or cable channel, provided that it has a digital TV tuner. The picture wouldn't be degraded by the extra steps, because the data is digital. However, the encoder/modulator (not sure what the proper term is for this) is apparently too expensive to include economically in a standalone digital STB, and all HDTVs have either component-video or HDMI inputs or (usually) both, anyway.

I have a Vizio 32" plasma hooked to an indoor antenna. It pretty much gets the stations I want. However it does bring is a few "phantom channels", digital channels, when I do a can. For example it tells me it found channels 27-7 and 27-8. But going to those channels brings up 'no signal' response, unsurprising since these channels don't exist. And it does this consistently. That is, rescanning always brings up the same phantom channels. Any ideas on why this might be happening? Is the tuner in the Vizio too sensitive and some interference has it confused? Or is the tuner faulty? Any thoughts on correcting this behavior?

As a comparison, I use a Samsung DTB-H260F and a tuner from my Panasonic 3576 DVD recorder in another room. Since this room is one floor up I get more "good" (ie, valid) digital stations but with none of the phantoms.


Thanks.


_Larry

I have a Vizio 32" plasma hooked to an indoor antenna. It pretty much gets the stations I want. However it does bring is a few "phantom channels", digital channels, when I do a can. For example it tells me it found channels 27-7 and 27-8. But going to those channels brings up 'no signal' response, unsurprising since these channels don't exist. And it does this consistently. That is, rescanning always brings up the same phantom channels. Any ideas on why this might be happening? Is the tuner in the Vizio too sensitive and some interference has it confused? Or is the tuner faulty? Any thoughts on correcting this behavior?

As a comparison, I use a Samsung DTB-H260F and a tuner from my Panasonic 3576 DVD recorder in another room. Since this room is one floor up I get more "good" (ie, valid) digital stations but with none of the phantoms.


Thanks.


_Larry

What channels do you normally recieve OTA? Might be getting some sort of intermod interference, though with digital ...? I'm more of an analog kind of guy and thus just speculating. Hard to know though without knowing what channels you normally receive. Also, are there any radio emitters near by? I'm not just talking about big radio towers, but cell transmitters, VHF/UHF radio transmitters, etc.

I currently get the usual slew of local digital/analog OTA stations. But it is just with this Vizio it is reporting the existence of 4-5 additional stations which simply don't exist. Again my other digital receivers behave just fine.

As for potential interference, the only thing remotely possible is the existence of some 80-100' tower a few blocks away that has antenna-like/satellite stuff on it. It is located at my county's central police headquarters. I thought perhaps this tower only had transmission receivers. But maybe such a place would broadcast signals too???

It was my understanding that Vizio's had excellent tuners. Perhaps they are "too excellent" by picking up interference?


Thanks.


_Lazza

Vizio tuners suck. Channels must be scanned, no direct entry allowed. QAM channels without any PSIP sometimes can't be received, and sometimes will make the tv freeze up, requiring unplugging to reset it.

Phantom channels could be caused by flawed PSIP data by a station. It might be caused by non tv services being carried on a channel, such as the pay reading service for the blind carried by some PBS stations.

Well that ship has sailed as I already have the 7698, just not installed yet. Please keep fingers crossed. I'm going to pray to the reception gods and hope I haven't changed what I got, I'm thinking instead of stamps I will just have a good start on a antenna collection. I will get update out when weather breaks a tad and can get up tower safely. Ice and tower climbing don't mix well. I do have an installer and we discussed stuff and he thought the 7698 would be a good move. I purchased antenna from amazon so he didn't have a big vested interest in selling etc.
Just an update on above post. I did not upgrade antenna but did decide to upgrade rotor to a Yaesu G800SA, I will if needed go to a Winegard YA-1713 as I did not want to gamble with a signal degrade. I do like the reception I am getting but a faulty rotor was a big part of problem. I will now let the world take a few spins with new rotor.

First I should admit I haven't read through the whole thread, but I did read the first 2-3 pages! :)

I was just checking on what I would need to get OTA HD up and running. I just bought and HDTV (with built in tuner) so I wanted to get over the air signal. Our house already has an old antenna and I checked www.antennaweb.org and 2150.com for stations. It looks like I should be able to get the main networks and PBS which is all I expected.

What else do I need? I think the antenna on the roof has the old style two wires connection, do I need to get up there and put on a different kind?

I assume that my old TiVo series 2 will not record signal so I would have to buy a TiVo HD right?

And other than that I should be fine for getting signal...at least that is what I think so far. Am I missing something?

Thanks,

Not sure. You omitted your location in your profile, so I can't tell where you're from. Is your antenna VHF or a combo? Post transition, some of your stations may be VHF or UHF or a mixture of both. Check your local thread for more.

But, I'd definitely replace the twinlead with RG-6 coax and, depending on your location and the distance from the transmitters, a preamp.

Now go back and read through the WHOLE thread <G>

Not sure. You omitted your location in your profile, so I can't tell where you're from. Is your antenna VHF or a combo? Post transition, some of your stations may be VHF or UHF or a mixture of both. Check your local thread for more.

But, I'd definitely replace the twinlead with RG-6 coax and, depending on your location and the distance from the transmitters, a preamp.

Now go back and read through the WHOLE thread <G>


Sorry. I am Cedar Rapids, Iowa.

As for the antenna....it is on the roof and that is high! So I haven't even taken a look at it. I am working through the CR thread right now but it is long! I had no idea there were that many people from eastern Iowa who posted.

What type of splitter do I need to split out my OTA antenna?

I just use a one input 2 output regular splitter made for outdoors that i got at a good old RS (I think). i didn't notice any signal loss. some of the posters might say there is but I don't notice any; my coax runs are relatively short; if you have long coax runs it might make a difference. They're not expensive so all you can do is try.

Using one dipole antenna on an Insignia CECB, tuned to one UHF station in the afternoon locked in a clear signal. Adjacent to that hookup was an RCA model ANT145 VHF/UHF dipole/loop antenna with an inner plate and a fine tuning knob on a Pal Plus tuned to the same UHF station locked into the same clear signal at the same time. Daytime weather was clear and sunny, little wind.

That night with a small amount of rain barely coming down and a bit more of a breeze, I turned on my tv and to my surprise, neither box received any signal from the station that had come in clear that afternoon.

I had to experiment with pointing the antennas in various direction for some time before a picture was received, and for the first 15 minutes or so, the picture broke up. About fifteen minutes into the program, the picture reception was almost as steady as it was earlier in the day. (The rain had stopped and there was less of a breeze.)

What puzzled me was how different the position of the antenna was inorder to get the same degree of reception as earlier in the day.

I had the two antennas about twelve inches from each other with identical angular position of the dipoles, and both the Insignia and Pal Plus held the station's picture with almost identical strength.

I had a concern that the proximity of the antennas to each other might interfere with the reception on one or both of them, but it didn't seem to matter. The tuners/boxes were about two feet from each other and were at different levels from each other. I didn't know if the UHF loop/plate position would affect the dipole antenna connected to the Insignia.

With the RCA antenna, I don't understand the relationship between the dipoles and the UHF loop/plate for receiving the signal from the UHF station. I have to have the dipoles pointed in a particular direction at a particular angle yet I also have to have the "plate" for the UHF loop angled in a particular way to get the signal also - if I leave out one of these things, the station doesn't come in, or, at least, not as well.

What I have learned is that OTA reception from these converter boxes is going to be dependent on atmospheric conditions more than I'd like. I'd think that stations with a digital signal lower in the number assignment would result in a signal less affected by weather conditions since the signal transmission consists of longer wavelengths.

It seems that it is in the nature of these converter boxes, given the nature of digital transmision OTA, for reception to deteriorate proportional to deteriorating weather conditions. How do people in the midwest and surrounding areas watch tv on nights when there is a tornado in the area? The warning on the tv screen might not even be viewable. : O

Using one dipole antenna on an Insignia CECB, tuned to one UHF station in the afternoon locked in a clear signal. Adjacent to that hookup was an RCA model ANT145 VHF/UHF dipole/loop antenna with an inner plate and a fine tuning knob on a Pal Plus tuned to the same UHF station locked into the same clear signal at the same time. Daytime weather was clear and sunny, little wind.

That night with a small amount of rain barely coming down and a bit more of a breeze, I turned on my tv and to my surprise, neither box received any signal from the station that had come in clear that afternoon.

I had to experiment with pointing the antennas in various direction for some time before a picture was received, and for the first 15 minutes or so, the picture broke up. About fifteen minutes into the program, the picture reception was almost as steady as it was earlier in the day. (The rain had stopped and there was less of a breeze.)

What puzzled me was how different the position of the antenna was inorder to get the same degree of reception as earlier in the day.

I had the two antennas about twelve inches from each other with identical angular position of the dipoles, and both the Insignia and Pal Plus held the station's picture with almost identical strength.

I had a concern that the proximity of the antennas to each other might interfere with the reception on one or both of them, but it didn't seem to matter. The tuners/boxes were about two feet from each other and were at different levels from each other. I didn't know if the UHF loop/plate position would affect the dipole antenna connected to the Insignia.

With the RCA antenna, I don't understand the relationship between the dipoles and the UHF loop/plate for receiving the signal from the UHF station. I have to have the dipoles pointed in a particular direction at a particular angle yet I also have to have the "plate" for the UHF loop angled in a particular way to get the signal also - if I leave out one of these things, the station doesn't come in, or, at least, not as well.

What I have learned is that OTA reception from these converter boxes is going to be dependent on atmospheric conditions more than I'd like. I'd think that stations with a digital signal lower in the number assignment would result in a signal less affected by weather conditions since the signal transmission consists of longer wavelengths.

It seems that it is in the nature of these converter boxes, given the nature of digital transmision OTA, for reception to deteriorate proportional to deteriorating weather conditions. How do people in the midwest and surrounding areas watch tv on nights when there is a tornado in the area? The warning on the tv screen might not even be viewable. : O

It has nothing to do with the converter boxes themselves, per se. It's simply due to atmospheric degradation of the signal during weather events itself when you are too close to the edge of the the "digital cliff".

The only way you can step back from the edge of that cliff is to improve your antenna system.

Besides, a typical TV antenna dipole is too long for efficient UHF reception as they are for VHF frequencies. If you use the proper antenna, your reception will improve.

about 2 months ago there was a listing or all the ota hd recievers available from direct tv and other places. Does someone.. ANYONE know where that went. I have looked for the last 3 days here now and I can't find it. Did it get merged with something else? this list had current and discontinued models on it. please point me in the right direction.

Do you mean the Official AVS HDTV STB Synopsis (http://www.avsforum.com/avs-vb/showthread.php?t=179095)? It's still here as a sticky post in this forum.

I must be going blind yes that is it. Thank you

I live in hole. I have a 30 ft mast antenna on the house with amp and motor but still only get 1 channel very badly. All the equipment is at least 20 years old. My friends at the top of the hill get 3 channels well with a pair of rabbit ears. My question is could I put an antenna up on the hill behind my house and run 400 feet of cable to the house. I can only get network channels through Dish and they come from 500 miles away and cost $11 a month.

I live in hole. I have a 30 ft mast antenna on the house with amp and motor but still only get 1 channel very badly. All the equipment is at least 20 years old. My friends at the top of the hill get 3 channels well with a pair of rabbit ears. My question is could I put an antenna up on the hill behind my house and run 400 feet of cable to the house. I can only get network channels through Dish and they come from 500 miles away and cost $11 a month.

first replace the coax cable and balun on your current system, they may have deteriorated with age. also aim your antenna tilted up a bit, aiming is best done while someone is watching the desired stations.

yes you could run 400 feet of cable and use an amplifier.

Can someone point me to a good thread that describes PC ATSC tuners and/or reviews? I'd like to add one to my computer for OTA reception/display, preferably one that can show data stream and/or signal diagnostics. Any thoughts on the Hauppage line? Thanks in advance for suggestions.

Try the HTPC section here: http://www.avsforum.com/avs-vb/forumdisplay.php?s=&daysprune=60&f=26

Especially the sticky threads. I usually go to the "How to build" thread for all the latest recommendations.

Try the HTPC section here: http://www.avsforum.com/avs-vb/forumdisplay.php?s=&daysprune=60&f=26

Especially the sticky threads. I usually go to the "How to build" thread for all the latest recommendations.

Dr Don,
Thanks! Wow, there's a lot of information at that link. I'm on the jaw dropping side of the line there. :D
satcom