Los Angeles, CA - OTA [Text View] - Page 11

delsherif

02-16-07, 01:56 PM

Hi all, I have been reading the great AV forums for several months learning all I can in the new world of HDTV. This is my first post.

I’m in North Redondo Beach (90278) and have been happily receiving most OTA HD Broadcasts since Nov. All of the sudden the past 3 days reception of NBC (channels 4-1, 4-2, 4-4) are completely dead. All the other OTA HD channels get great reception (2-1, 5-1, 7-1 etc) During primetime TV the last several evenings, the TV tuner display on channel 4-1 said the signal is 70-80% strength “SD” with a BLANK screen for several seconds, than presented CBS (channel 2-1) in its place. Formerly I was able to watch most of prime time in HD with at least 70% strength. For example I was trying to tune in “Medium” the other night, I know this is presented in HD, but the TV was calling it “SD” signal with 80% strength and no picture would display. Same thing last night. I did the antenna dance to no avail…

By the way, NBC comes in fine SD through TWC cable with the internal NTSC tuner. (But analog SD on a HDTV is pretty disgusting)

At first I thought the NBC HD broadcast was down – but after several days I’m wondering if it’s not the TV tuner itself. Using an amplified Radio Shack internal antenna with 70-80% amplification, could the signal be so noisy it’s giving the tuner fits? Why only on NBC? And every NBC channel (4-1, 4-2, 4-4) is not working at all. Why all of the sudden after working for several months? Did NBC suddenly decide to encrypt the signal?

Any thoughts aside from the obvious (the tuner is dying)?

Equipment:
29 miles to Mt Wilson, no major obstructions
Astar LTV-27BG with NTSC/ATSC tuner
Radio Shack’s 15-1880 amplified combo VHF/UHF set-top indoor antenna mounted in window
OTA ATSC reception
Time Warner Cable NTSC reception (no external box)

qwert1515

02-16-07, 08:37 PM

Did you check to make sure the antenna has not moved?

Next try re-scaning your off the air channels, probably the tuners stored PSIP data is corrupted for NBC. NBC is not encrypting their signal, I can still receive it OTA.

jasonvr

02-16-07, 09:53 PM

Anyone have any idea why KABC is deciding to not to show Grey's Anatomy tonight and instead are showing America's Funniest Home Videos? The national feed is showing the rerun from last night (like usual), but the local feed is showing Americas Funniest Home Videos... :mad:

Edit:
Well, regardless of the fact that my guide, the KABC website, and TitanTV all list Americas Funniest Home Videos, Grey's Anatomy is on..... I guess you really can't believe what you read.

celticpride

02-17-07, 11:12 AM

does anybody receive HD channels in the victor valley high desert area using an antenna? i live in apple valley zip 92308.

yevlar

02-19-07, 12:45 AM

I assume I'm pretty much SOL here, but I'll ask anyway.

I live in Glendale, zip 91201, about a half mile south of the Verdugo hills. My view of Mt. Wilson is pretty much completely obscured by them.

I don't really watch much TV - I just got a small, cheap indoor antenna (regular old rabbit ears with a small amplifier) for the off-chance that I might want to watch something. I've identified several places in my apartment where I can actually get signal (never more than 1 major network at a time, though - I can get KCBS from the top of a bookshelf, KCET from the middle of my desk, KNBC about two feet further East, KCAL9 another 6 inches south, and occasionally KABC another foot south with the antenna hanging halfway off the desk. The channels that I would never watch, i.e. various Spanish-language channels and those four ION channels, usually come in fine at all these locations.)

I'm guessing that, due to my location, it's probably a miracle that I'm getting ANY digital channels at all, especially using an indoor antenna, but I thought I'd check here to see if anyone knows any tricks to receive slightly more reliable reception in this area.

RudyG

02-19-07, 05:28 PM

9xnet

02-20-07, 04:43 PM

I live in west LA 90024 and i installed a RS 2160 antenna on the roof, i connected it to my MCE PC according to antennaweb i should aim at 47° - 50° and i am 23.4 miles away.

I got reception of most channels but fox would be in and out, i noticed that i seemed to get better signal when i aim it closer to 60° which i thought was wired so i got a map out and mapped it to Mt Wilson and it does appear that 60° would be a more direct path then 47°.

Yesterday i took down the 5' pole and installed a 10' pole so it raised the antenna an additional 5' above the roof and installed a preamp , that and the preamp helped keep the signal and i get most channels green but i still get dropouts.

Do you think a dual / stack setup will work better, with two 2160? I just want to get this all working before i get a HDTV...

benway

02-21-07, 01:38 PM

did anyone else notice that the geniuses at NBC had a time/temp box on screen during Law and Order last night?

and they still havent fixed their center channel /low volume audio issues.

I wonder if they had these issues when they first started broadcasting in color? or when they went from radio to tv. :D

I've tried to find an email to write to them at, but they appear to have no customer service... as well as no engineering dept.

thanks

RudyG

02-21-07, 02:36 PM

Did a channel scan last night and found a new KCET subchannel 28.3. It looked to be 480i and had no audio on it. Is that just my TV or has anyone else seen this?

Rudy

MDRLou

02-21-07, 03:44 PM

PJO1966

02-21-07, 06:35 PM

Last night's American Idol was really pixelated, even during static shots. I don't think I've ever seen it that bad. Did anyone else see this?

qwert1515

02-21-07, 11:07 PM

American Idol did not look that great last night in HD, it does look much better tonight.

bichmgnt

02-22-07, 12:53 AM

I live in Oxnard 93035 near the mouth of the harbor so I'm about as far south as you can get in my area. Antennaweb says I have a view directly down the street toward Mt Wilson but also says I'll only get the standard def channels from there. Since my garage is on the street I can put an antenna out there that should get a fairly clear view. I'm in the middle of a remodel on my house and if I'm going to put up an antenna now is the time and spending money on it is not a problem. Anyone know what my chances are of getting HD signals in my particular area? If I can't get HD OTA it's not worth the effort of putting up an antenna at all except for FM.

I searched for info on Oxnard but most of what I found was either not very helpful or not very encouraging although a few posts suggested it might work.

Any help is appreciated.

Steve

holl_ands

02-22-07, 04:16 AM

9xnet

02-22-07, 06:39 PM

PJO1966

02-22-07, 08:24 PM

American Idol did not look that great last night in HD, it does look much better tonight.

Much better. I wonder what the problem was?

holl_ands

02-23-07, 12:33 AM

I got a CM-4228 today and installed it right under my RS 2160 and put a splitter / combiner before the preamp, i haven't seen to many breakups since i installed it a few hours ago, its raining pretty good out.

Do you think i would get better results with just the CM-4228?
If you are using a Lindsey Stripline Combiner (or equivalent) then combining two dis-similar antennas MAY
provide some useful combining gain under certain conditions....and only 0.2 dB insertion loss.
But antenna mis-match will still cause imperfect gain summing for some channels....

If you are using the usual RF Splitter in reverse, you've lost gain under nearly all conditions, compared to just the CM4228.

An RF Splitter/Combiner is a HYBRID device.
If the two inputs are EQUAL and IN-PHASE then up to 3 dB of combining gain can be realized.
However, with dis-similar antennas, this very rarely occurs. The mis-match is dissipated inside the HYBRID,
resulting in over 3 dB of insertion LOSS on each input....on TOP of the antenna gain mis-match....

bichmgnt

02-23-07, 11:17 AM

Here's a RADIO MOBILE coverage run for that area.
It's for KTTV-DT (FOX) being received with a medium-to-high gain outdoor antenna and a Preamp.
However, most LA stations will have similar results...at least you can see where the BAD spots are...

Looks like you are in the "Green" area--meaning you should have an adequate 20+ dB of Fade Margin.

I would recommend trying CM-7777 Preamp (usually on-line order) with CM-4228 8-Bay antenna (check Fry's).

BTW: Here's info re RADIO MOBILE free download and setup:
http://hdtv.forsandiego.com/messages/1/5427.html?1170794076
Holl_ands,

So yes, I do live in the green area on the attached pictures. Thanks for that. Didn't run the program but it seems fairly involved and I just don't have time to figure out the whole thing right now.

But essentially you're saying is that since I live in a green area for Fox's HD signal that the general coverage for the HD OTA channels is good enough for me to receive if I put up a good antenna with a pre-amp. Is that correct? What you're really saying is that Antennaweb is very conservative, right-wing even, possibly to the point of doing a disservice.

Thanks for the antenna suggestions. If I want to distribute the signal to 6 locations I should probably use an amplifier instead of a splitter. What would you suggest?

It is truly amazing the programs that are out there available for free to the public. I never would have guessed a program like Radio Mobile was out there. This forum is just as amazing. Thanks.

Steve

holl_ands

02-23-07, 07:04 PM

Here are (mostly) successful reports for Oxnard/Ventura area that may be of interest:
http://www.avsforum.com/avs-vb/showthread.php?p=8298768&highlight=oxnard#post8298768
http://www.avsforum.com/avs-vb/showthread.php?p=4362905&highlight=oxnard#post4362905
http://www.avsforum.com/avs-vb/showthread.php?p=8207112&highlight=ventura#post8207112
http://www.avsforum.com/avs-vb/showthread.php?p=7154158&highlight=ventura#post7154158
http://www.avsforum.com/avs-vb/showthread.php?p=6373348&highlight=ventura#post6373348

And a few reports posted on HDTVPUB:
http://www.hdtvpub.com/local/viewOTAReports.cfm/group_plasma-hdtv/zipcode_93035/dma_803/city_Oxnard/

It appears that the report re the outdoor Silver Sensor (low gain antenna!!!) may be same as the "friend in West Oxnard".
If they upgraded to an antenna with more gain/directivity, they should be able to greatly improve reception quality.

===========================================
Most of us find antennaweb.org will underestimate performance, even with the new and improved algorithms...
whatever they may be--apparently it's proprietary....

Some users find a better prediction by entering a much higher antenna height (say 200 or even 500-ft).
If you use the "options" tab on the address entry page and enter say 500-ft, you should find the list of LA DTV stations.
So you stand a fairly good chance (did I say YMMV???)

Whether or not you can actually receive L.A. stations will depend more on how well you can suppress signals from
the local towers so that they don't desensitize the Preamp via intermod products...and only certain channels will be affected.

Of course, YMMV, esp depending on how close you are to the local towers.
The south end of the harbor is better than the north in this respect cuz it's further away.

A high gain antenna pointed towards Mt Wilson (about 71-72 deg) will suppress some local stations
(31-34 deg, 15+ miles) in the deep sidelobe null.
And the other local stations (317-320 deg, 13+ miles) will be suppressed by the backlobe (Front-to-Back Ratio).

After doing some prelim signal level guesstimates, you should try the lower gain Winegard Preamp
(e.g. AP-4700), since it has higher resistance to overload desensitization than CM7777.

The only way to find out is to try....and use refund/return privileges if it doesn't work.

TheRock

02-24-07, 12:30 AM

Does anyone have a phone number for NBC's technical staff? Right now during Las Vegas there has been a constant white banner onscreen that tells what time it is and the current temperature. This has stayed on the whole time during the show and also the commercials. This is the second time I have seen this in the past week.

EDIT..

Finally went away after being onscreen for around 18 minutes.

It would still be nice to have a number to call if this happens again.

bichmgnt

02-24-07, 01:20 AM

Wow, you're good. Great info. As an engineer I appreciate the level of detail.

My particular location may naturally suppress the local stations since I live in a one-story ranch surrounded by two- and three-story homes. I do have line of site to Mt Wilson down the street from the front of my garage (at least according to Antennaweb) so I'm thinking that will be my only real source for coverage. Although if the local antennas are only 13-15 miles away they may interfere anyway.

I'll take your advice on the pre-amp and set up for my install. I've yet to get the TV and am in the middle of wiring the house for AV/audio/ethernet/security system so it may be a bit before I actually can pull the system together but I'll let you know how it works.

Thanks again.

Steve

DSperber

02-24-07, 01:27 AM

Does anyone have a phone number for NBC's technical staff?

It would still be nice to have a number to call if this happens again.818-840-3799

DSperber

02-24-07, 01:42 AM

I noticed that the small very faint almost transparent (making it VERY VERY NICE) KTTV-DT "Fox HD" logo in the lower-right corner during American Idol which was present on Tuesday and Wednesday had been changed on Thursday to a new larger whitish kind of swooping "FOX" logo, shaped sort of like a slightly concave-on-both-sides lens graphic, like they have on their "Widescreen" promos and lead-ins). I prefer the old small nearly invisible logo.

I also had a very strange anomaly with my JVC DT100U, trying to record some snippets from AI to D-VHS (from my TWC 6412 DVR). I recorded (or thought I recorded) about 10 minutes from Tuesday, and another 10 minutes from Wednesday. When I went to play it back on Thursday it was as if the VCR had not even moved from the point on the tape that I know it was started from (the tail end of another recording).

And yet, I had used the very same DVR/VCR to make three hours of recordings from ABC-DT earlier in the day (different tape, of course) without a problem. And after I discovered the recording failure I experimented with the same very same tape (that had failed to record AI from Fox-DT) to record something off of CBS-DT and had no problem! Same tape, same starting spot on the tape, no failure this time. I also tried to record something from the Thursday night AI, and again... no failure this time. (maybe it was the new logo???)

Its as if the OTA Fox-DT broadcast on Tuesday and Wednesday was "copy never", although it was recordable to the DVR so that doesn't fly. Interestingly, I did ensure that the VCR was seeing the digital data (via firewire) being played back from the DVR before I pushed the REC button, but then went back to watching through the DVR rather than waiting a bit longer when I possibly might have seen the "CANNOT RECORD" error message.

Anyway, this was very odd, and I'm sorry to have lost those 20 minutes of AI (as I then deleted the programs from the DVR, before checking the tape as I usually do). But it's really as if the recorder didn't record, and didn't even move the tape, even though the display meter was progressing normally for both of those 10 minute sessions.

Very strange. I will see what happens next week if I do this again.

Anybody else notice this? Surely Fox-DT didn't do this to try and prevent HD tape copies of the show. And they didn't protect Thursday's show, if my experience is somehow related to 5C.

Surely it's got to be something with my VCR and/or tape. Maybe the tape was "stuck", and then "un-stuck". But I'm surprised the motors and display on the VCR continued to make sound and progress normally, as if the recording was happening normally. And the red REC light was lit.

Very very strange. Again, I recorded successfully to tape before and after the failing recording session, on both days. Only those two 10 minute Fox-DT recordings from those two AI shows failed to record.

TheRock

02-24-07, 02:36 AM

818-840-3799

Thanks.

dj4monie

02-25-07, 02:25 AM

Can anybody in the Reseda, Northridge, Tarzana area suggest a company to install a Channel Master or another good UHF HDTV antenna?

I can't get any HD channels back in my room, but when you hook up a set of rabbit ears to my father's Direct HD-DVR, all 18 local channels are available. 90% of them come in, the one most important to me is FUNmantion's Anime channel on 18.3

I can get it on the DVR, but my Cat's Eye card can't get anything. I have trouble with VHF out here as well. The antenna in the garage is no help at all.

So I'll need to have one installed or do it myself. I would like to have somebody come out and do it for a reasonable price.

Any suggestions or should I just get a Channel Master and do it myself???

dj4monie

02-27-07, 01:26 AM

Okay on Wed my day off Im going to try something that should work.

Direct TV Multi-Switches are also Duplexers. I can run the UHF signal from an outdoor antenna into the Multi-switch and then use another duplexer to split the signal again. One back to my D*tv box and the UHF signal to my Vbox card.

I'll update when I get it up and running.

Rick_R

02-27-07, 12:28 PM

joe221

02-27-07, 10:53 PM

I think we need an update here's what I have:

Engineering Dept:

KCBS - 323-460-3416
KNBC - 818-840-3799
KTLA - 323-460-3917
KABC - 818-863-7468
KTTV - 310-584-3335

Bringing it down to here.

dj4monie

02-28-07, 02:15 AM

dj4monie,

Another thing to try is a better indoor antenna. The Silver Sensor is highly recommended. It is often available at Circuit City. I have seen it at the Cricuit City in Woodland Hills.

Reseda should get OTA with an indoor antenna unless you have something in your house construction blocking it. I saw indoor antennas in Ken Cranes on Ventura Blvd getting digital channels.

Rick R

Thanks Rick...

Here's what I did...

I was using the signal meter that comes as a untility with the VBox drivers. It constantly bounced around between -3000 and "0"

I took back the RCA Amp'ed Antenna and got Indoor/Outdoor Antenna from Radio Shack. It comes with a Univ mount and 10db gain amp. I also bought a Duplexer/Spliter.

Again using WatchHDTV and the Signal Meter, I got no picture. I put the new antenna in the same location as the one connected to my father's HD-DVR.

I moved it outside, the meter improved but still didn't generate a graph.

I though maybe I messed up the install of the card, so I went into the device manager. Everything looked fine, but I un-installed everything, restarted and it found the updated drivers I downloaded before the restart. I also downloaded BTV4 again (I used it late last year when I had having MMC problems).

After the re-start, it installed the newest drivers from the folder and Windows said it was A-Okay. I installed BTV4, let it setup the Vbox as the only tuner. Well it started finding ALL the channels. I can't seem to find KTLA, or I might not be looking, but it found all 18 local HDTV channels!

After it finished and intialized, it tuned to KCBS-DT and wouldn't you know -

CSI: Las Vegas in 1080i :D

Law & Order: Special Victums Unit in 1080i :D

FUNmation in 480p :D

Now the antenna location on the window sill isn't the best. Im going to mount it outside and I should get even better signal quality. FUNmation studders just a bit and I know its the antenna location. It does it on the HD-DVR as well, but otherwise its "Beyond" watchable and stable 95% of the time.

Rick -

The problem in my room is my window is less than 6 ft from the cinder block retaining wall. Plus there 2 bushes on either side of the window and a tree. The tree has no leaves at the moment but VHF has trouble back here.

Out in the backroom, that same wall is 15-20ft from the window and otherwise nothing is blocking the path of the signal.

Well in my room the wiring is temp and a mess. So im going to mount the antenna out on the roof of the backroom and point it directly at Mount Wilson!

That should solve the minor studdering issue I have with FUNmation.

Run a cable back to the Mutliswitch and clean up the wiring in here. Otherwise I finally get to enjoy HDTV, how I want and when I want.

Now that I can get an HD signal back here, I guess it time to put the other drives in and install MCE.

The VBox is easy to install, just add drivers and the proper viewing software and your ready to go.

Fooie to all those on "The Green Button" that said I would have problem watching HD content because I have ATI AIW 9600XT 128mb card and slower P4 2.4Ghz CPU...

Now back to watching - Pandalian on FUNmation!

dj4monie

02-28-07, 02:43 AM

Have I mentioned how deinterlacing the picture makes FUNmation look 100% smoother???

Im using the Cyberlink decoder at the moment.

HDTVFanAtic

02-28-07, 03:29 AM

dj4monie

02-28-07, 04:39 AM

Not if you plan on using the HD Ka satellites.

Im quite sure when the installer comes ova to put in my HD box, he'll use the 5 LNB dish already out there, not the 1 LNB dish in the front of the house. My HD signal is coming from the Analog 1 LNB dish/Multiswitches....

Thank you for your concern...

Rick_R

02-28-07, 01:48 PM

I am sure that the cinder block wall has steel rebar that inhibits reception. However bushes should have little effect. My son lives in Valley Village in a second floor apartment. I set up his digital TV reception an used an FM twin lead antenna and got all digital channels when I taped it to the wall.

Rick R

RudyG

03-01-07, 02:44 AM

Did a channel scan last night and found a new KCET subchannel 28.3. It looked to be 480i and had no audio on it. Is that just my TV or has anyone else seen this?

Rudy

Well it looks like we are about to get a new OTA channel. This wasn't fluke after all. KCET is rolling out a new channel, albeit in Spanish. :) It will start transmitting in March of this year. Here is the link to the website:
http://www.v-me.tv/

Rudy

ml248

03-01-07, 03:20 PM

I live on the Sherman Oaks/Van Nuys border near the corner of Burbank Blvd. and Kester Ave. I've been using an OTA antenna that I got from DirecTV, but I only can get channel 4.1 using it. Does anyone have any recommendations on a new antenna to get? I appreciate any advice.

SgtBulldog

03-01-07, 06:56 PM

I'm using the Philips PHDTV3 (new Silver Sensor) in Atwater Village and have great reception. I think it's on sale at Amazon right now if you want it cheap.

twelvepbrs

03-01-07, 07:16 PM

I'm using the Philips PHDTV3 (new Silver Sensor) in Atwater Village and have great reception. I think it's on sale at Amazon right now if you want it cheap.
looking at the pictures is the phillips PHDTV3 simply a PHDTV1 encased in plastic, plus dipoles and an amp?

SgtBulldog

03-01-07, 09:19 PM

Yep, it is exactly as you describe it.

mkpl

03-02-07, 12:54 AM

RudyG

03-04-07, 01:50 PM

...
11-1 (KTTV) comes in rarely. I have never had 13-1 (KCOP) show up. Are these two channels generally hard to pick up?
....
What my tuner picks up appears to be highly dependent on the direction my silver sensor is pointing. It is very difficult to find a sweet spot that picks up all the channels and even then some of them will have higher reception gain than others. Sadly they are not all transmitted at the same angle from Mt. Wilson.
The reception is also highly dependent on the weather. :) During high winds I consistently see drop outs on my OTA channels.

Rudy

andy.s.lee

03-04-07, 02:33 PM

I live east of Mission Viejo and have a Radio Shack U-75R in my attic, along with a 10dB amp near the antenna. There is also a large furnace in the attic, and the antenna is a few feet to the north of it. With this setup I can consistently pick up:
2-1 (KCBS)
4-1 (KNBC)
5-1 (KTLA)
9-1 (KCAL)
18-1 (KSCI)
22-1 (KWHY)
30-1 (ion)
34-1 (KMEX)
40-1 (KTBN)
46-1 (KFTR)
50-1 (KOCE)
52-1 (KVEA)
54-1 (KAZA)
56-1 (KDOC)
58-1 (KLCS)

Usually these also come in (and seem to be consistent since I replaced the RG-59 cable with RG-6):
7-1 (KABC)
28-1 (KCET)

11-1 (KTTV) comes in rarely. I have never had 13-1 (KCOP) show up. Are these two channels generally hard to pick up?

I've had 10-1 (KGTV San Diego) show up, and on one scan 38-1 (KPMR) and 38-2 (KTSB) out of Santa Barbara registered, but had no picture.
See attached file for a radar plot of channels in your area. Longer bars indicate stronger channels. Transmitter details are listed to the right of the plot.

Mission Viejo is a very hilly area, so the available channels at your exact location will depend on what terrain obstructions are present in your neighborhood. A more accurate analysis can be done with a specific latitude, longitude, and antenna height.

Based on this generic analysis alone, it looks like all the Mt. Wilson channels should be very easy (with the green background), including KTTV and KCOP. However, you'll notice that KTTV and KCOP are transmitted on RF channels 65 and 66, respectively. One reason you might be having problems with these channels is that they are at the high end of the UHF spectrum, perhaps at a frequency where your U-75R antenna's gain is starting to fall off. Out of curiosity, have you ever received KRCA, 62.1, on RF channel 68?

Best regards,
Andy

andy.s.lee

03-04-07, 03:52 PM

What my tuner picks up appears to be highly dependent on the direction my silver sensor is pointing. It is very difficult to find a sweet spot that picks up all the channels and even then some of them will have higher reception gain than others. Sadly they are not all transmitted at the same angle from Mt. Wilson.
The reception is also highly dependent on the weather. :) During high winds I consistently see drop outs on my OTA channels.

Rudy
The transmitters on Mt. Wilson are packed pretty close to each other, so for most people in the area, the transmitters have a very small angular spread. If you look at the radar plot in my previous post, you can see that at Mission Viejo distances, the transmitters are within half a degree of each other.

Actually, the symptoms your describing sounds like multipath. Multipath is when multiple copies of a single transmission are received at your antenna due to various reflections / diffraction that is occurring in the environment. Your antenna may pick up the line-of-sight (LOS) transmission along with copies of the same signal reflected off of a mountain, a tall building, or even parts of your own house. Each of the extra signal images will arrive with varying amounts of delay because the time-of-flight will vary with the different paths travelled.

With analog TV, this kind of effect shows up as ghost images. That's because an analog TV simply throws everything it receives onto the screen and you can actually see all the multipath signals combined right on the picture.

With digital TV, things are a little different. The ATSC signal is a stream of digital data. If your receiver is able to decode that data stream, then you get a nice clean picture on your screen. If the receiver cannot decode the data stream, you get no picture at all. For the most part, getting a digital channel is an all or nothing proposition. There's not much to "see" between a digital channel working and not working.

With the digital signals, simultaneously receiving a delayed copy of a signal is equivalent to having two transmitters on the same frequency jamming each other. Multipath actually results in each channel interfering with itself due to those extraneous reflected signals. Being in a location with very strong signals does not necessarily make things any better (and in fact can make things worse) because environments bathed in strong signals are also subject to strong multipath signals.

The way to beat multipath is to try and avoid receiving the unwanted multpath signals. There are generally two ways about this:

1) Relocate the antenna to a place with less multpath effects. For example, it may be possible to move the antenna to a side of the house that is shielded from the dominant signal reflectors in the environment. Installing the antenna higher (e.g., attic or roof) usually helps too because that puts it above some of the multipath "clutter" amongst the buildings below.

2) Use a directional antenna to isolate cleaner signal paths. The radiation pattern "beam width" of directional antennas can sometimes pick out a clean signal while mostly ignoring unwanted multipath signals. Note that people usually use this technique to pick up the LOS signal (pointing at the transmitter), but in some cases, a reflected signal off a mountain or tall building will have less clutter. It all depends on your particular location and environment.

One of the great challenges of multipath is that it is very unpredictable and will change with the environment. Things like moving objects, humidity, rain, sun spots, and other factors can affect the number and strength of multipath signals reaching any particular point in space. Every situation is unique, so it will take a little bit of planning to come up with an antenna configuration that minimizes your susceptability to changing multpath conditions.

If you're having difficulty getting consistency with your indoor Silver Sensor, placing it higher might help a bit (top of bookshelf, second floor, attic, etc.). Of course, you'd have a lot better control with a more directional antenna in the attic or on the roof, but you'll have to use your own judgement as to what's appropriate for your particular situation.

Best regards,
Andy

holl_ands

03-04-07, 05:54 PM

mkpl

03-05-07, 01:15 AM

...However, you'll notice that KTTV and KCOP are transmitted on RF channels 65 and 66, respectively. One reason you might be having problems with these channels is that they are at the high end of the UHF spectrum, perhaps at a frequency where your U-75R antenna's gain is starting to fall off. Out of curiosity, have you ever received KRCA, 62.1, on RF channel 68?

I don't recall ever pulling that one in.

I also had a private reply noting that my antenna's high end is weak, which goes along with my poor reception of channels above 61.

Can you provide a more precise position, such as some nearby cross streets???

A little southeast of Santa Margarita Pkwy and Melinda. My elevation is around 1050 feet.

RudyG

03-05-07, 01:30 AM

The transmitters on Mt. Wilson are packed pretty close to each other, so for most people in the area, the transmitters have a very small angular spread. If you look at the radar plot in my previous post, you can see that at Mission Viejo distances, the transmitters are within half a degree of each other.

I live in West Los Angeles. Zip Code 90025. Here are my coordinates: Latitude: 34° 2 Min. 29 Sec.
Longitude: -118° 27 Min. 59 Sec.

Actually, the symptoms your describing sounds like multipath. Multipath is when multiple copies of a single transmission are received at your antenna due to various reflections / diffraction that is occurring in the environment. Your antenna may pick up the line-of-sight (LOS) transmission along with copies of the same signal reflected off of a mountain, a tall building, or even parts of your own house. Each of the extra signal images will arrive with varying amounts of delay because the time-of-flight will vary with the different paths travelled.

Sorry, I'm not sure that I agree with you on that. That is that the symptoms I'm describing are in fact multipath, but then again I'm not exactly an expert. :) What I can tell you is that when I point my Silver Sensor more north I get one set of channels and when I point my antenna more west I get another set of channels. The channels that do come in are in the 80% signal strength. If they were all transmitted at the same angle, wouldn't they all be deflected by whatever object is deflecting the subset of them? No?

With analog TV, this kind of effect shows up as ghost images. That's because an analog TV simply throws everything it receives onto the screen and you can actually see all the multipath signals combined right on the picture.

With digital TV, things are a little different. The ATSC signal is a stream of digital data. If your receiver is able to decode that data stream, then you get a nice clean picture on your screen. If the receiver cannot decode the data stream, you get no picture at all. For the most part, getting a digital channel is an all or nothing proposition. There's not much to "see" between a digital channel working and not working.

Yup I actually knew that.

With the digital signals, simultaneously receiving a delayed copy of a signal is equivalent to having two transmitters on the same frequency jamming each other. Multipath actually results in each channel interfering with itself due to those extraneous reflected signals. Being in a location with very strong signals does not necessarily make things any better (and in fact can make things worse) because environments bathed in strong signals are also subject to strong multipath signals.

The way to beat multipath is to try and avoid receiving the unwanted multpath signals. There are generally two ways about this:

1) Relocate the antenna to a place with less multpath effects. For example, it may be possible to move the antenna to a side of the house that is shielded from the dominant signal reflectors in the environment. Installing the antenna higher (e.g., attic or roof) usually helps too because that puts it above some of the multipath "clutter" amongst the buildings below.

2) Use a directional antenna to isolate cleaner signal paths. The radiation pattern "beam width" of directional antennas can sometimes pick out a clean signal while mostly ignoring unwanted multipath signals. Note that people usually use this technique to pick up the LOS signal (pointing at the transmitter), but in some cases, a reflected signal off a mountain or tall building will have less clutter. It all depends on your particular location and environment.

Isn't Silver Sensor highly directional?

One of the great challenges of multipath is that it is very unpredictable and will change with the environment. Things like moving objects, humidity, rain, sun spots, and other factors can affect the number and strength of multipath signals reaching any particular point in space. Every situation is unique, so it will take a little bit of planning to come up with an antenna configuration that minimizes your susceptability to changing multpath conditions.

If you're having difficulty getting consistency with your indoor Silver Sensor, placing it higher might help a bit (top of bookshelf, second floor, attic, etc.). Of course, you'd have a lot better control with a more directional antenna in the attic or on the roof, but you'll have to use your own judgement as to what's appropriate for your particular situation.

Sadly I live in an apartment, but will definitely take suggestions on the antenna and placement. Indoor would be good but outdoor is an option as well. One of the great challenges for me is aiming the antenna and seeing the signal strength without having to run to my TV every 30 seconds. However, the signal strength meters that I have seen cost hundreds of dollars. :( I tell you one thing this OTA business seems more of a black art really.

Best regards,
Andy
Thank Andy.
Rudy

andy.s.lee

03-05-07, 02:49 AM

A little southeast of Santa Margarita Pkwy and Melinda. My elevation is around 1050 feet.
That's still not detailed enough to provide a precise analysis since the hills in the area cause TV reception to change so rapidly (see attached map). Things can be good on one block and bad on the next block over.

But from the description in your earlier message about all the channels you're able to receive, it sounds like you're far enough up on the hill to the south-east of Santa Margarita and Melinda that you're probably seeing Mt. Wilson with a line-of-sight view. If that's the case, then the earlier analysis tells enough of the story and exact coordinates aren't necessary.

Best regards,
Andy

ilopezc

03-05-07, 03:15 AM

Hi,

Ive been thinking about trying to get some HDTV action in my Area of San Juan Capistrano.

Ive been using AntennaWeb and it seems that DT channels are not present for my specific address/location, however about 1/4 mile east AntennaWeb reports a bunch of DT channels.

Is my location too far down in the valley to pick up such transmissions, would I have no hope even with a High Gain Directional Antenna since Im so far away from the transmitters?

Lat: 33.5165329 Lon: -117.6664276 - Google Earth says that Im about 200ft above sea level, my house is one story, and my City Ordinance says I can have an antenna no higher than 12 feet. Is it possible to receive DTV channels from even here? I guess Ill try and grab a UHF Antenna + Pre-Amp to see if the OTA channels come in ok.

Thanks for everyones help in advance.

Also where would I ask what are the best USB ATSC receivers?

jeff2631

03-05-07, 03:53 AM

You would need a 45 meter tall antenna to clear the hill where Paseo de Colinas is on.

andy.s.lee

03-05-07, 06:10 PM

I live in West Los Angeles. Zip Code 90025. Here are my coordinates: Latitude: 34° 2 Min. 29 Sec.
Longitude: -118° 27 Min. 59 Sec.
Attached is a plot for your location. The Mt. Wilson transmitters are within a 3 degree angular spread of each other.

Sorry, I'm not sure that I agree with you on that. That is that the symptoms I'm describing are in fact multipath, but then again I'm not exactly an expert. :) What I can tell you is that when I point my Silver Sensor more north I get one set of channels and when I point my antenna more west I get another set of channels. The channels that do come in are in the 80% signal strength. If they were all transmitted at the same angle, wouldn't they all be deflected by whatever object is deflecting the subset of them? No?
Nope. That's another aspect of multpath that makes it such a challenge to clean up. Multipath is caused by the cumulative effects of attenuation, reflection, refraction, and diffraction of signals between the source and the destination. All of these properties vary with frequency (e.g., reflection coefficient on various materials will change as a function of wavelength). Although it's quite common for large solid objects to affect signals in a similar way (e.g., mountains, big buildings), there are many other multipath contributors that vary by frequency, hence the net sum at your antenna can be different depending on channel.

Self interference is only one of the side-effects of multipath. Another side-effect that engineers often need to contend with is fading. When multiple RF signals cross at a point in space, they may be in a state of constructively or destructively interfering with each other. This can cause narrow-band frequency selective dips in power, especially indoors or in urban environments. See Rayleigh fading (http://en.wikipedia.org/wiki/Rayleigh_fading) on Wikipedia.

It suffices to say that when lots of multipath is around, it can have lots of detrimental effects, it is frequency selective, and it's exact behavior is unpredictable. These kinds of effects are nothing new nor unique to TV. These things also affect cell phones, GPS, WiFi, and a whole lot of other RF technologies we take for granted. The problem gets worse for indoor and urban environments and sometimes special measures must be taken (see Diversity schemes (http://en.wikipedia.org/wiki/Diversity_scheme)).

Isn't Silver Sensor highly directional?
It is somewhat directional. It has a radiation beam width of about 60 degrees as seen here:
http://www.hdtvprimer.com/ANTENNAS/silveraz.gif

An example of an even more directional antenna is the Channel Master 4228 with a beam width of about 30 degrees as seen here:
http://www.hdtvprimer.com/ANTENNAS/cm4228az.gif

In addition to beam width, another consideration is the front-to-back ratio (some antenna designs have narrow beam widths, but also have some gain going out the opposite side). This is another measure of how "selective" an antenna is. An antenna with very high gain in only one direction and very low gain in every other direction will have a better chance of picking out a specific transmission path.

Sadly I live in an apartment, but will definitely take suggestions on the antenna and placement. Indoor would be good but outdoor is an option as well. One of the great challenges for me is aiming the antenna and seeing the signal strength without having to run to my TV every 30 seconds. However, the signal strength meters that I have seen cost hundreds of dollars.
Rooftop is usually the best option. Signal strengths are usually stronger up there, plus you benefit by being above most of the multipath clutter caused by the buildings below. Once on the roof, it's also easier to switch to a larger, more directional antenna. When you add up all the benefits, it makes overcoming multipath a lot easier. Each situation is unique, so you might be able to do just fine with a more modest antenna setup.

The signal strengths in your area are quite strong, so your Silver Sensor may be a perfectly fine solution if you could just find the right location and orientation to make it work for all the channels all the time. If I were you, I'd start by experimenting with the antenna placed in different parts of the apartment or place it higher up. If you still can't find a satisfactory solution, then it might be time to consider something outdoors or more directional.

Having a signal meter is a luxury that is probably not necessary for the majority of situations (it certainly wouldn't hurt if you don't mind spending the money). They can help with aiming antennas at transmitters, however, most situations are forgiving enough to allow for a +/- 10 degree slop in the adjustment (most antenna beam widths are even bigger than this) without a problem. If a system is so close to the edge of working that a signal meter is needed to get it right, that means there's very little margin for error and there's a good chance that the system will stop working once the weather gets bad or something else causes the multipath environment to change.

I tell you one thing this OTA business seems more of a black art really.
Outdoors is real easy. The problem is that we insist on bringing our TVs, cell phones, and other wireless gadgets indoors and into urban environments (how silly of us :)). Multipath is a fact of life and we just need to do what we can (refer to diversity link above) to make our gadgets work in these RF challenged environments.

I guess the silver lining is that at least with your TV, you have the option of only moving your antenna to an "easy" spot while leaving the main unit in a convenient location for you to enjoy. Just try doing that with your cell phone.

Best regards,
Andy

andy.s.lee

03-05-07, 07:08 PM

Ive been thinking about trying to get some HDTV action in my Area of San Juan Capistrano.

Ive been using AntennaWeb and it seems that DT channels are not present for my specific address/location, however about 1/4 mile east AntennaWeb reports a bunch of DT channels.

Is my location too far down in the valley to pick up such transmissions, would I have no hope even with a High Gain Directional Antenna since Im so far away from the transmitters?

Lat: 33.5165329 Lon: -117.6664276 - Google Earth says that Im about 200ft above sea level, my house is one story, and my City Ordinance says I can have an antenna no higher than 12 feet. Is it possible to receive DTV channels from even here? I guess Ill try and grab a UHF Antenna + Pre-Amp to see if the OTA channels come in ok.
You would need a 45 meter tall antenna to clear the hill where Paseo de Colinas is on.
jeff2631 is correct in saying that the line-of-sight signal paths are passing over your house at about 45 meters above ground (see "LOS_hgt" in attached radar plot).

However, I don't think I'd give up hope yet. Radio waves have the ability to bend around objects slightly via diffraction. Based on my estimates, the obstructing hill next to Paseo de Colinas is about 3000 meters away from you. At this distance, the diffraction angle is about 1 degree, which is shallow enough that a usable amount of signal should still be able to reach your house.

In order to optimize signal, you'll want to place the antenna as high as possible (e.g., 10' mast on roof) with a high gain antenna pointed directly at the ridgeline between you and Mt. Wilson. It sounds like you were about to experiment with an antenna already, so I guess you'll soon find out.

BTW, by FCC rules, you may install an OTA antenna up to 12' above the roofline and no local ordinance can restrict you to anything less than that. Refer to this FCC FAQ (http://www.fcc.gov/mb/facts/otard.html) on the subject.

Good luck!

Best regards,
Andy

TitanFan

03-05-07, 08:08 PM

ilopezc

03-06-07, 02:05 PM

@Titan local noise maybe?

Thanks everyone for helping me. I made a crude directional antenna, but this was only designed for the VHF not the UHF band. I'm able to pick up about 6 broadcast channels with CH5 the best looking.

I also got Radio Mobile working and made a map for my location + overlayed it in google earth.

Now the VHF (ie 79Mhz) may come in just fine, but isnt path loss become greater with frequency and distance? Also I ventured on my roof, and I have some very tall trees greater than 20 ft. So while the VHF may get reflected about so I can get a nice signal (but no ghosting). Im worried that the higher UHF frequencies will get attenuated.

Also, has anyone experimented with passive repeaters?

andy.s.lee

03-06-07, 03:40 PM

I have an OTA antenna mounted to my chimney pointed toward Mt. Wilson. I live in North Orange County. I have strong reception on all channels with many at 100% on my digital tuners. I've split my antenna signal to my DirecTV HR20 and my HD Sony TV. I noticed a strange thing with the OTA reception of KVMD channel 23. Both the HR20 and Sony TV report a signal strength of greater than 90 on channel 23.1, but I don't get a picture. Also, I can get channel 23.3 on the TV's tuner, but I can't get it on my HR20. My TV and HR20 are getting the same OTA antenna signal!! I don't have this issue with any other station. Any ideas?
FYI, KVMD is not located on Mt. Wilson. They broadcast from Twentynine Palms to the east. With your antenna pointed at Mt. Wilson, you're probably not going to get a good signal from KVMD.

Best regards,
Andy

andy.s.lee

03-06-07, 07:00 PM

Now the VHF (ie 79Mhz) may come in just fine, but isnt path loss become greater with frequency and distance? Also I ventured on my roof, and I have some very tall trees greater than 20 ft. So while the VHF may get reflected about so I can get a nice signal (but no ghosting). Im worried that the higher UHF frequencies will get attenuated.
Yes, path loss is higher for higher frequencies. However, broadcasters in UHF usually transmit with more power than broadcasters in VHF for that very reason. The net effect is that most broadcasters originating from the same place have substantially similar coverage footprints due to this transmit power compensation. The lower frequency channels might bounce and skip extra far on a good day, but the primary coverage area (FCC service contour curves) of each broadcaster should be similar to their peers. In other words, in an open space, the field strength of most of the major channels will be about the same.

Since you live in an area in the shadow of a hill, the propagation differences between VHF and UHF will start to become more pronounced. Some of the more observable effects include:
- Lower frequencies will diffract energy at greater angles than higher frequencies.
- Higher frequencies usually have more attenuation (from trees, building materials, etc.) than lower frequencies.
- Lower frequencies are more susceptible to Fresnel diffraction losses (skimming horizontally close to the ground).
- Higher frequencies reflect more strongly than lower frequencies.

Your measurements will be the combined effects of all of these (and other) environmental influences. Since it's hard to say what factors are affecting you the most, it's not immediately obvious whether VHF or UHF will be stronger for you. The diffraction and reflection effects are probably the most dominant factors, but you'll just need to experiment to see what you really get.

Best regards,
Andy

twelvepbrs

03-06-07, 07:53 PM

TitanFan

03-06-07, 08:12 PM

FYI, KVMD is not located on Mt. Wilson. They broadcast from Twentynine Palms to the east. With your antenna pointed at Mt. Wilson, you're probably not going to get a good signal from KVMD.

Best regards,
Andy

Yes, I know KVMD is broadcast from Twentynine Palms. So, why is my signal strength meter showing >90 for KVMD if my antenna is not pointing in that direction?

holl_ands

03-06-07, 08:18 PM

twelvepbrs

03-06-07, 09:04 PM

RF signals only "bend" over long distance paths, via atmospheric refraction.
What you'll get are signals bouncing THROUGH building windows, etc
and reflections off of mostly nearby buildings. Envision a really, really powerful
spotlight shining through and against paper buildings.....

What's your zipcode and nearby cross-streets???
7810 topanga canyon blvd (i don't mind throwing the address out here bc/it's a big apartment complex) it's near saticoy and the zip is 91304

andy.s.lee

03-06-07, 09:31 PM

does anyone have a uber-rough estimate of how much (degrees) the paths for UHF signals could bend? i'm on the 1st floor of a 2 story apt building, and my patio faces mt wilson, but there is another two story building about 100-150 feet away, meaning that i'd need the signal to bend about 15 degrees is this hoping for way too much?
Diffraction over opaque objects like mountains have properties similar to knife-edge diffraction (a semi-technical tutorial can be found here (http://www.mike-willis.com/Tutorial/diffraction.htm)). The energy does fall off as the angle of diffraction increases (see graph near bottom of tutorial). That function is actually dependent on frequency. Longer wavelength can "bend" further than shorter wavelenths. In the case of TV, diffracted energy will fall off below usable levels very quickly (within a couple of degrees). 15 degrees is out of the question.

HOWEVER, in your situation, I wouldn't worry about diffraction at all. From the perspective of RF signals, buildings are semi-transparent, reflective, and full of holes. The net signal that you receive is the sum of all path loss, reflection, refraction, diffraction, and attenuation effects between the transmitter and your antenna. Diffraction may be important if you are behind a mountain obstruction, but in almost all other situations, diffraction becomes negligible compared to the other factors.

You don't need to worry about that other building creating a "black hole" with no signal behind it. I suspect that plenty of RF signal will make it through, in, and around the buildings in your neighborhood.

...also does anyone have any good links other than antenna web to lookup OTA reception maps with terrain data? or perhaps google earth files with reception data?
I'll post a response to your message with the address...

Best regards,
Andy

andy.s.lee

03-06-07, 09:50 PM

7810 topanga canyon blvd (i don't mind throwing the address out here bc/it's a big apartment complex) it's near saticoy and the zip is 91304
Attached is a radar plot of digital channels in the area. Longer bars represent stronger signals.

There really aren't any terrain obstructions between you and Mt. Wilson. I think your biggest problem will be coping with multipath (all the different paths going through, in, and around everything to reach your antenna), which can make DTV signals difficult to decode.

Multipath is nearly impossible to predict, but based on the information seen so far, you might have an easy time getting these channels with something like the indoor Silver Sensor antenna. You should probably try it and report back if you encounter any problems.

Best regards,
Andy

twelvepbrs

03-06-07, 10:20 PM

Attached is a radar plot of digital channels in the area. Longer bars represent stronger signals.

There really aren't any terrain obstructions between you and Mt. Wilson. I think your biggest problem will be coping with multipath (all the different paths going through, in, and around everything to reach your antenna), which can make DTV signals difficult to decode.

Multipath is nearly impossible to predict, but based on the information seen so far, you might have an easy time getting these channels with something like the indoor Silver Sensor antenna. You should probably try it and report back if you encounter any problems.

Best regards,
Andy
Andy, thanks a ton for the info, i already have a jensen indoor antenna with an amp (which is pretty crappy from what i've read on AVS), picks up KTTV, KTLA, KCBS, but kinda iffy on KNBC, and KCAL. The antenna is about as high and as close to my patio window as possible, but there is a large tree right in front of it, so i'm thinking of getting a tv-tuner card, and moving the antenna to my bedroom where my pc is and just recording video, and then playing it back to my tv; the view towards mount wilson is much less-obstructed from my bedroom (no tree), i noticed that the image you posted has almost all of the stations with an azimuth of 88º-90º, should this directly correspond to a compass reading? because antennaweb.org showed that all the channels have a compass orientation of around 75º for me; is it safe to assume the general rule of higher is always better for the antenna placement?
also, and this is a question for everyone, do the local stations vary their broadcast power throughout the day? so far it seems like signals are stronger during primetime (unless this has something to do with the atmosphere in the evening)
I'm getting ready to get rid of my dig-cable since my apt comes with free basic, and there are clear-qam for the local HD's but they seem to change/go in-out everyday, so i wanna get my OTA situ setup before i dump catv

andy.s.lee

03-07-07, 01:02 AM

i noticed that the image you posted has almost all of the stations with an azimuth of 88º-90º, should this directly correspond to a compass reading? because antennaweb.org showed that all the channels have a compass orientation of around 75º for me
The azimuth on the radar plots and tables are relative to true north, like on a map. You can compute the difference between true north and magnetic north using this NOAA site (http://www.ngdc.noaa.gov/seg/geomag/jsp/Declination.jsp).

...i already have a jensen indoor antenna with an amp (which is pretty crappy from what i've read on AVS), picks up KTTV, KTLA, KCBS, but kinda iffy on KNBC, and KCAL. The antenna is about as high and as close to my patio window as possible, but there is a large tree right in front of it, so i'm thinking of getting a tv-tuner card, and moving the antenna to my bedroom where my pc is and just recording video, and then playing it back to my tv; the view towards mount wilson is much less-obstructed from my bedroom (no tree)...

...is it safe to assume the general rule of higher is always better for the antenna placement?
The signals are so strong in your area that it's unlikely that you will have signal strength issues (due to trees or other blockage). You are more likely experiencing multipath interference. Since the signal can take so many different paths to reach your antenna, the combination of all those different paths makes the signal interfere with itself, thus making it hard for your receiver to decode the channel. There are a few things you can do to help make things better:

- Use a more directional antenna. Your Jensen antenna is probably more of an omnidirectional antenna, meaning that it will take in signal from many directions (all the multipath clutter) and pass that through to your TV. A directional antenna is mostly sensitive in one direction only and ignores signal coming from most other directions. This can help you pick out a single clean signal path and get less of the unwanted extra multipath signals. This provides a cleaner signal for your TV to decode. Note that the cleanest path is not always the one with the antenna pointed toward the transmitter.

- Move the antenna higher and into places less prone to multipath. Usually, as you move an antenna up (second floor, attic, roof, etc.), you get above some of the multipath crosstalk amongst the buildings below. This also usually has the effect of grabbing stronger signals and causing one of the clean signal paths to rise above most of the other interfering signals.

As long as you can raise your signal to interference ratio (SIR) and signal to noise ratio (SNR) sufficiently, you should be able to get nice clean DTV reception. Yes, it is usually better to move the antenna higher, but a good antenna with correct orientation might get you what you want without forcing you to do so.

I hope this helps. Good luck!

Best regards,
Andy

andy.s.lee

03-07-07, 01:57 AM

Yes, I know KVMD is broadcast from Twentynine Palms. So, why is my signal strength meter showing >90 for KVMD if my antenna is not pointing in that direction?
There are a few things that come to mind:

- There's a difference between signal strength and signal quality. If the signal is strong but has heavy interference, then your receiver won't be able to decode it and you won't get a picture. Pehaps your antenna is picking up the line-of-sight signal combined with a strong multipath reflection since it is not pointed at KVMD. The combined signal might be strong, but not clean.

- It's not clear how the HR20 comes up with the number representing signal strength. Most receiver manufacturers do not actually report true power level indicators. If they did, then I could take white noise, amplify it up to high power, and it would count as a very strong signal. That's probably not the case for the majority of receivers out there.

- Instead, what the receiver makers usually do is estimate signal quality by looking at signal to interference ratios (e.g., correlator processing gain or similar measures, for you DSP gurus out there) and/or decoder bit error rate estimates. By guesstimating how well the radio is "locked on" to the channel and how well the data stream is being decoded, the receiver might come up with a number representing how well it thinks everything is working. However, the scale and meaning of these numbers can be completely arbitrary. A high score does not necessary correlate with "strong" in the usual sense of the term. It's also not clear whether a high score has anything to do with the stability or reliability of a channel.

I can't really say why your receiver is reporting a signal strength of 90. If we ignore that number for a moment, perhaps the simple thing to do is try pointing the antenna at KVMD and see what happens.

In any case, I'd say you're already getting a wonderful selection of ATSC channels. How important is it to get this one additional channel? :)

Best regards,
Andy

ilopezc

03-07-07, 03:36 AM

Yes, path loss is higher for higher frequencies. However, broadcasters in UHF usually transmit with more power than broadcasters in VHF for that very reason. The net effect is that most broadcasters originating from the same place have substantially similar coverage footprints due to this transmit power compensation. The lower frequency channels might bounce and skip extra far on a good day, but the primary coverage area (FCC service contour curves) of each broadcaster should be similar to their peers. In other words, in an open space, the field strength of most of the major channels will be about the same.

Since you live in an area in the shadow of a hill, the propagation differences between VHF and UHF will start to become more pronounced. Some of the more observable effects include:
- Lower frequencies will diffract energy at greater angles than higher frequencies.
- Higher frequencies usually have more attenuation (from trees, building materials, etc.) than lower frequencies.
- Lower frequencies are more susceptible to Fresnel diffraction losses (skimming horizontally close to the ground).
- Higher frequencies reflect more strongly than lower frequencies.

Your measurements will be the combined effects of all of these (and other) environmental influences. Since it's hard to say what factors are affecting you the most, it's not immediately obvious whether VHF or UHF will be stronger for you. The diffraction and reflection effects are probably the most dominant factors, but you'll just need to experiment to see what you really get.

Best regards,
Andy

Thanks Andy!

Im going to go try OTA soon.

-Israel

holl_ands

03-07-07, 10:22 AM

I have an OTA antenna mounted to my chimney pointed toward Mt. Wilson. I live in North Orange County. I have strong reception on all channels with many at 100% on my digital tuners. I've split my antenna signal to my DirecTV HR20 and my HD Sony TV. I noticed a strange thing with the OTA reception of KVMD channel 23. Both the HR20 and Sony TV report a signal strength of greater than 90 on channel 23.1, but I don't get a picture. Also, I can get channel 23.3 on the TV's tuner, but I can't get it on my HR20. My TV and HR20 are getting the same OTA antenna signal!! I don't have this issue with any other station. Any ideas?
CH23 is a shared channel: KTBN-DT on Mt Wilson, KVMD-DT high on a mountain
overlooking Riverside and XETV-DT in Tijuana.

So you may have strong signals, but they are interfering with each other....
And one receiver may be more tolerant of co-channel interference than the other....

Moving the antenna around, trying to point a null towards undesired station, may help...

jimcrow21

03-07-07, 03:40 PM

twelvepbrs

03-07-07, 04:44 PM

I started watching KCAL9 again after a 2-3 month hiatus, using my OTA tuner. I heard the Laker games started broadcasting in HD starting early Feb, and even during the short breaks of the Laker game of I was watching (Lakers @ Timberwolves) KCAL said they were broadcasting the game on HD (for TWC, but it was implied that it might be broadcasted OTA).

Despite all they said, I only saw the game in SD (Upscaled to 1080i with black pillar bars). I heard from others as well that some of OT1 was in HD but i didn't see any part of the game in HD. Are the games usually in HD OTA (I don't have TWC, so I don't really care if you got it in HD with cable). Thanks for the input.
I think i read on another forum that only the home games are in HD, sorry i don't have a cite, but i've definitely seen bits of the lakers games on KCAL in HD via OTA and TW, they may just be saying that all the lakers games are in HD because well PR people are stupid; if you check here:
http://www.hdsportsguide.com/nba.php
it looks like the only games listed for KCAL are lakers home games

EvilEuro

03-07-07, 04:54 PM

I think i read on another forum that only the home games are in HD, sorry i don't have a cite, but i've definitely seen bits of the lakers games on KCAL in HD via OTA and TW, they may just be saying that all the lakers games are in HD because well PR people are stupid; if you check here:
http://www.hdsportsguide.com/nba.php
it looks like the only games listed for KCAL are lakers home games

KCAL has all non-network Laker ROAD games, so it would be all Laker road games that are in HD. I have seen every game that KCAL has shown since the switch and they've all been in HD.

Fox Sports West has all non-network Lakers home games and it's dependent upon whether or not your provider gives an HD feed of Fox Sports West to determine if you can see those games in HD. So far as I know they're not showing them in HD, but then again, even if they were I wouldn't be able to tell because Dish Network isn't providing an HD feed of FSW.

jimcrow21

03-07-07, 07:14 PM

KCAL has all non-network Laker ROAD games, so it would be all Laker road games that are in HD. I have seen every game that KCAL has shown since the switch and they've all been in HD.

Fox Sports West has all non-network Lakers home games and it's dependent upon whether or not your provider gives an HD feed of Fox Sports West to determine if you can see those games in HD. So far as I know they're not showing them in HD, but then again, even if they were I wouldn't be able to tell because Dish Network isn't providing an HD feed of FSW.

"Every" game since the transition, literally? I've got a couple of people on my other thread (HDTV Programming) saying they saw what I saw, an SD version of last night's game (@ Minnesota).

Just got an email response from KCAL:

Thank you for taking time out of your day to send your remarks
regarding
Lakers in HD on KCAL 9. Due a technical difficulty, last night's game
was not broadcast in HD. Normally, we broadcast over the air HD for
Lakers. In April, KCAL 9 will be available in HD as well.

Connie McKibbin
Programming Administrator
KCAL 9

Don't know what she means by "KCAL 9 will be availible in HD as well." I'm guessing she means news, unless they plan to broadcast everything in HD like PBS, though that is practically impossible.

twelvepbrs

03-07-07, 07:24 PM

holl_ands

03-07-07, 08:58 PM

CH23 is a shared channel: KTBN-DT on Mt Wilson, KVMD-DT high on a mountain
overlooking Riverside and XETV-DT in Tijuana.

So you may have strong signals, but they are interfering with each other....
And one receiver may be more tolerant of co-channel interference than the other....

Moving the antenna around, trying to point a null towards undesired station, may help...
For what it's worth, at mkpl's location in N-E Mission Viejo, KTBN-DT and XETV-DT are within a couple dB in
signal strength and KVMD-DT is about 30 dB lower....per RADIO MOBILE.

YMMV....

joe221

03-08-07, 02:21 AM

Interestingly, tonight's game (Wed) it started in HD with the announcers then switched to SD. Go figure!
:confused:

RudyG

03-08-07, 05:41 AM

Attached is a plot for your location. The Mt. Wilson transmitters are within a 3 degree angular spread of each other.

Thank you for the plot map. Great info. Although I have some questions regarding that. So let me setup the first question. Here are the channels I receive without a problem (signal strength 80+ and no major breakups during bad weather)
KCBS
KTLA
KABC
KTTV
KLCS

Here are the stations that will break up a little in bad weather but mostly hang on to the signal.
KVCR
KCET
KOCE

Here are the stations that sometimes break up in good weather and all but dissappear in bad
KNBC - (The weakest of all)
KCAL
KCOP

Now I studied the plot that you attached and noticed that KNBC is broadcast at measly 296kW so I though perhaps that is why it comes in so weakly, however, KLCS is transmitted at an unbelievable 26kW and yet it comes in fine. On top of that KCOP is blasted at the highest kilowatt rating in the list 835 and yet I have a lot of trouble locking onto that signal. What could the explanation be for such erratic reception behavior?

My second question about the chart is what is Rx_dBm?

Nope. That's another aspect of multpath that makes it such a challenge to clean up. Multipath is caused by the cumulative effects of attenuation, reflection, refraction, and diffraction of signals between the source and the destination. All of these properties vary with frequency (e.g., reflection coefficient on various materials will change as a function of wavelength). Although it's quite common for large solid objects to affect signals in a similar way (e.g., mountains, big buildings), there are many other multipath contributors that vary by frequency, hence the net sum at your antenna can be different depending on channel.

Self interference is only one of the side-effects of multipath. Another side-effect that engineers often need to contend with is fading. When multiple RF signals cross at a point in space, they may be in a state of constructively or destructively interfering with each other. This can cause narrow-band frequency selective dips in power, especially indoors or in urban environments. See Rayleigh fading (http://en.wikipedia.org/wiki/Rayleigh_fading) on Wikipedia.

It suffices to say that when lots of multipath is around, it can have lots of detrimental effects, it is frequency selective, and it's exact behavior is unpredictable. These kinds of effects are nothing new nor unique to TV. These things also affect cell phones, GPS, WiFi, and a whole lot of other RF technologies we take for granted. The problem gets worse for indoor and urban environments and sometimes special measures must be taken (see Diversity schemes (http://en.wikipedia.org/wiki/Diversity_scheme)).

It is somewhat directional. It has a radiation beam width of about 60 degrees as seen here:
http://www.hdtvprimer.com/ANTENNAS/silveraz.gif

An example of an even more directional antenna is the Channel Master 4228 with a beam width of about 30 degrees as seen here:
http://www.hdtvprimer.com/ANTENNAS/cm4228az.gif

In addition to beam width, another consideration is the front-to-back ratio (some antenna designs have narrow beam widths, but also have some gain going out the opposite side). This is another measure of how "selective" an antenna is. An antenna with very high gain in only one direction and very low gain in every other direction will have a better chance of picking out a specific transmission path.

A question about this antenna and my location. According to the chart I'm less than 30 miles from the transmission source and this antenna is very much a long range antenna. Is that going to be a problem?

Rooftop is usually the best option. Signal strengths are usually stronger up there, plus you benefit by being above most of the multipath clutter caused by the buildings below. Once on the roof, it's also easier to switch to a larger, more directional antenna. When you add up all the benefits, it makes overcoming multipath a lot easier. Each situation is unique, so you might be able to do just fine with a more modest antenna setup.

The signal strengths in your area are quite strong, so your Silver Sensor may be a perfectly fine solution if you could just find the right location and orientation to make it work for all the channels all the time. If I were you, I'd start by experimenting with the antenna placed in different parts of the apartment or place it higher up. If you still can't find a satisfactory solution, then it might be time to consider something outdoors or more directional.

Having a signal meter is a luxury that is probably not necessary for the majority of situations (it certainly wouldn't hurt if you don't mind spending the money). They can help with aiming antennas at transmitters, however, most situations are forgiving enough to allow for a +/- 10 degree slop in the adjustment (most antenna beam widths are even bigger than this) without a problem. If a system is so close to the edge of working that a signal meter is needed to get it right, that means there's very little margin for error and there's a good chance that the system will stop working once the weather gets bad or something else causes the multipath environment to change.

Outdoors is real easy. The problem is that we insist on bringing our TVs, cell phones, and other wireless gadgets indoors and into urban environments (how silly of us :)). Multipath is a fact of life and we just need to do what we can (refer to diversity link above) to make our gadgets work in these RF challenged environments.

I guess the silver lining is that at least with your TV, you have the option of only moving your antenna to an "easy" spot while leaving the main unit in a convenient location for you to enjoy. Just try doing that with your cell phone.

Best regards,
Andy
I'm guessing that this chaos of transmitting signals at different angles and different kW is due to the fact that every station must do their own transmitting. Makes me wonder if it is technologically possible to transmit everything from a single tower, at the same angle, same kW.

Thanks Andy.
Rudy

RudyG

03-08-07, 05:44 AM

RudyG

03-08-07, 05:49 AM

Andy, thanks a ton for the info, i already have a jensen indoor antenna with an amp (which is pretty crappy from what i've read on AVS), picks up KTTV, KTLA, KCBS, but kinda iffy on KNBC, and KCAL. The antenna is about as high and as close to my patio window as possible, but there is a large tree right in front of it, so i'm thinking of getting a tv-tuner card, and moving the antenna to my bedroom where my pc is and just recording video, and then playing it back to my tv; the view towards mount wilson is much less-obstructed from my bedroom (no tree), i noticed that the image you posted has almost all of the stations with an azimuth of 88º-90º, should this directly correspond to a compass reading? because antennaweb.org showed that all the channels have a compass orientation of around 75º for me; is it safe to assume the general rule of higher is always better for the antenna placement?
also, and this is a question for everyone, do the local stations vary their broadcast power throughout the day? so far it seems like signals are stronger during primetime (unless this has something to do with the atmosphere in the evening)
I'm getting ready to get rid of my dig-cable since my apt comes with free basic, and there are clear-qam for the local HD's but they seem to change/go in-out everyday, so i wanna get my OTA situ setup before i dump catv

Remember I ended up taking my Silver Sensor outside onto the patio. It is still under the roof but instead of being behind the window it is now in front of the window.
You'll need lots of patience if you are planning on undertaking this antenna pointing business. ;) ;) Lots of patience.

Good Luck.
Rudy

danki6x

03-08-07, 11:44 AM

Don't know what she means by "KCAL 9 will be availible in HD as well." I'm guessing she means news, unless they plan to broadcast everything in HD like PBS, though that is practically impossible.
I believe you are correct. The KCAL/KCBS HD News studio is to be ready about then. So both channels news will be HD about then.

Kiwijonesy

03-08-07, 12:08 PM

EvilEuro

03-08-07, 01:27 PM

Hello,

I live in Costa Mesa (92626) and have just ordered DirectV HD. One of the staions I will be losing is "THE TUBE NETWORK" and am wondering if I can pick it up with an OTA. It is currently available on the afflilate station KTLA-TV5 Digital Tuner 5.5 but when I searched my zip on Antennaweb i did not see the station listed. Is anyone here getting this station and if so which OTA are you using or would you recomend. I live in a single story house with no trees, buildings or hills.

Thanks in advance.

I live a bit north of you in North Orange County, but in an area with hills and tall trees between myself and Mt. Wilson. The Tube comes in blazing strong for me.

I have two different antennas working HD at my house. One is an RCA VR-75 on my roof for my main TV. In my bedroom I have a Silver Sensor that I finally got set to the right point and KTLA never comes in at below 90 on my signal meter for either television.

The Tube kicks ass. It's like the MTV of my youth, only without Alan Hunter and Nina Blackwood ruining the goodness that was Martha Quinn, JJ Jackson and Mark Goodman. Oh yeah, and a much better selection of music too.

Kiwijonesy

03-08-07, 02:13 PM

EvilEuro

03-08-07, 02:17 PM

Excellent. Yeah "The Tube Network" is very cool especially if you are 40+ in age. I am watching videos of some of my favorite music that I did now even existed.

Do you think I would get away with a Silver Sensor in my Attic?

I have mine on top of an armoire, but I've read of lots of people using it in the attic to help with multipath issues. Just make sure you take a compass up there with you to set it pointing in the proper direction and then hold it down with something like QuakeGrip or some other tacky substance. Otherwise you run the risk of the thing moving around and getting off target.

holl_ands

03-09-07, 04:54 AM

I'm guessing that this chaos of transmitting signals at different angles and different kW is due to the fact that every station must do their own transmitting. Makes me wonder if it is technologically possible to transmit everything from a single tower, at the same angle, same kW.

Thanks Andy.
Rudy
When you design antennas in close proximity, they not only interact due to perturbations of the
antenna patters, but can also have intermodulation and even overheating problems from all of that
off-frequency energy being crammed down a waveguide and INTO the output tube that were
designed for an optimized VSWR at some other operating frequency....OUCH!!!!

The CN-Tower in Toronto, Empire State Building and other similar structures were forced to
address these problems head-on:
http://www.lnl.com/esbantennas.htm
However, note that they end up being extremely tall, co-linear stacks of many individual antenna structures.

BTW: DTV Transmit antennas must have much closer control of VSWR and frequently use a receiver
to monitor the transmitter's output and automatically generate compensating correction signals.
This is needed since reflections up and down the waveguide act as additional multipath, degrading
your ability to receive the signal....esp. tuners built more than a couple years ago....

========================================
Here's some photos of the Mt Wilson antenna farm with multiple FM/TV/DTV antennas per stick:
http://www.well.com/user/dmsml/wilson.html
http://www.earthsignals.com/Collins/0035/index.htm
and another antenna farm about 1/2-mile south, lower down on Mt Harvard.

It's something that has slowly evolved over the past 60 years, although some stations share the same tower.
What, you expect these fierce competitors to actually cooperate????

RudyG

03-12-07, 05:14 PM

.....
What, you expect these fierce competitors to actually cooperate????
I suppose that would be one option. Another option would be for either you or me to build the Master Tower and then lease the signal transmitting services to the networks. :D

Rudy

P.S. By the way some great pictures there.

csrini1

03-15-07, 01:23 AM

andy.s.lee

03-15-07, 07:09 PM

Now I studied the plot that you attached and noticed that KNBC is broadcast at measly 296kW so I though perhaps that is why it comes in so weakly, however, KLCS is transmitted at an unbelievable 26kW and yet it comes in fine. On top of that KCOP is blasted at the highest kilowatt rating in the list 835 and yet I have a lot of trouble locking onto that signal. What could the explanation be for such erratic reception behavior?
Most likely, it's because of multipath. One of the ironies of OTA reception is that sometime stronger signals makes things harder to receive. When you are close to a strong transmitter, your house and everything around it are swimming in strong signals. This actually increases the number and strength of multipath reflections that might reach your antenna.

It's a little like the way you should avoid turning on your high-beams while driving on a foggy night. You can sort-of see ok with low-beams, but switching to high-beams causes increased light scatter and actually makes things harder to see.

Since multipath varies with frequency, the hot and cold spots may be at different locations for the various channels. You might get a "weak" channel to become "strong" and vice versa by moving the antenna around or pointing it in a different direction. Keep in mind that the signal strength meter on your receiver is probably not really a measure of true signal "strength", but rather a measure of signal "quality". All the signals in your area are pretty strong, but some of them might be prone to worse multipath interference than others. If you are still having a hard time fighting multipath, then it's probably time to consider moving the antenna higher and possibly to the attic or roof.

The reason for the variation between broadcasters is mostly because of the choice of directional antennas they are using (there's no point pumping a lot of energy into the Angeles National Forest and the mountains behind Mt. Wilson). Most of the broadcasters are transmitting with similar total power levels, but due to the antenna selection and exact orientation of the main lobe of the antenna pattern, you'll see slightly different power levels being sent in your particular direction.

Even through 296 kW sounds like a lot of power compared to 26 kW, it's only about a 10.5 dB difference (in power, everything is on a 10*log10 scale), which is why you see the ~10 dB difference in the Rx_dBm column. The total spread of all the channels is not that much (~20 dB), so I don't think the variations in transmit power you're seeing will actually matter much. The fact that all the channels are quite strong (above -70 dBm) means that the small differences in channel power will matter even less.

My second question about the chart is what is Rx_dBm?
That is the predicted field strength of the signal at a hypothetical point in space (your receive antenna's coordinates). Knowing the transmit power of each broadcaster, their antenna pattern, and their frequency, we can compute the estimated signal loss over the terrain and through the air to reach you. The results are converted to dBm units, which is something you might read directly off a spectrum analyzer when looking at these signals.

Since these estimates are for a virtual point in space, the actual signal reaching your TV tuner depends on everything in your "RF chain", including your antenna's gain, any amplifier gains, cable losses, splitter losses, etc. The plots will tell you what's "in the air", and it's up to you to fill in the blanks for everything between "the air" and your receiver.

Based on my own experiences and the feedback from others who have used these simulations, I would generally categorize channels as follows:

- Channels above about -70 dBm are very strong and there's a good chance they can be picked up with an indoor antenna (although indoors is the most vulnerable location for multipath interference)

- Channels between about -70 and -100 dBm are where signals are getting weaker and the antenna will probably need to move to a better location (attic or outdoor) in order to receive it.

- Channels below about -100 dBm are getting difficult to receive and are best served by a rooftop or mast mounted antenna.

- With high gain antennas (e.g., XG91, DAT-75, CM 4228) and a good installation (i.e., appropriate pre-amps, quality cables, etc.), it should be possible to receive channels down to about -110 dBm, give or take.

Of course, these are very rough estimates and every situation is different, so multipath, co-channel interference, adjacent channel interference, overload constraints, and a slew of other factors must be considered in order to understand the challenges facing any specific setup. The simulation software, the plots, and the tables are merely tools to help us make more informed decisions, but are by no means meant to be taken as gospel.

A question about this antenna and my location. According to the chart I'm less than 30 miles from the transmission source and this antenna is very much a long range antenna. Is that going to be a problem?
I don't consider the Silver Sensor to be a long range antenna. It is directional, but the actual gain of the antenna is not that high. The antenna pattern plots are scaled to the highest gain point of the antenna, but do not actually show the total gain of the device. The Silver Sensor has a maximum gain of approximately 7 dBi, whereas an antenna like the CM 4228 has a maximum gain of approximately 16 dBi, which is more typical of what people think of as "long range" antennas.

In either case, I don't think there's enough gain in the antenna to cause any problems for you. The signals are indeed strong, so I would recommend that you DO NOT install any amplifiers in your RF chain. An amplifier could have overloading problems since it has to simultaneously amplify so many strong channels in the spectrum. Your tuner, on the other hand, should be fine with these power levels, since it only looks at one channel at a time, and any one channel's power is not high enough to cause any problems. Even a high gain antenna would not pull in enough signal to be a problem for your tuner.

Best regards,
Andy

andy.s.lee

03-15-07, 08:17 PM

Andy, I live in area code 91007 and from antennaweb.org, looks like i am within 8 miles of transmission. I am using indoor Silver Sensor antenna, philips phdtv1, guess what, it picked up 30 channels at one point(all sorts of them), BUT it did not get ABC,FOX,CHANNEL13. Do i need to go with terk antenna(indoor) or the higher version from philips phdtv3??
See attached radar plot for analysis results.

My interpretation:

- KTTV (Fox) and KCOP are transmitting from just behind Mt. Harvard. Mt. Harvard actually blocks several of the Mt. Wilson transmitters, creating a shadow around most of your neighborhood. KTTV (digital on RF channel 65) and KCOP (digital on RF channel 66) are right behind the mountain, making it pretty difficult to receive. Since you only provided a zip code, I arbitrarily picked a point in the zip code for the simulation. You may get different results based on your exact coordinates and relationship to Mt. Harvard.

- According to the coordinates I happened to pick, KABC is not blocked and I would expect you to pick up KABC just fine. It should be very strong like the others, so you might be having difficulty due to multipath. You may be able to get this channel simply by moving your antenna around or pointing it in a different direction.

Since there is significant signal blockage in the area, you'll need to provide a more specific location to get more accurate results.

If the coordinates I used are pretty accurate, then I'd say that KTTV, KCOP, and possibly KABC are being blocked by Mt. Harvard. I would NOT change antennas. With this kind of blockage, I don't think you'll do any better with a different antenna. In fact, if you are really deep into the shadow zone, the only way you're likely to get these channels is with a rooftop antenna.

If you were just a couple of miles to the east, west, or south, you'd be out of the shadow and get all the channels, but with your current location, I'd say you're out of luck on a few channels. If you are willing to install a rooftop antenna, then you should be able to manage receiving a few more channels.

Best regards,
Andy

csrini1

03-15-07, 10:50 PM

See attached radar plot for analysis results.

My interpretation:

- KTTV (Fox) and KCOP are transmitting from just behind Mt. Harvard. Mt. Harvard actually blocks several of the Mt. Wilson transmitters, creating a shadow around most of your neighborhood. KTTV (digital on RF channel 65) and KCOP (digital on RF channel 66) are right behind the mountain, making it pretty difficult to receive. Since you only provided a zip code, I arbitrarily picked a point in the zip code for the simulation. You may get different results based on your exact coordinates and relationship to Mt. Harvard.

- According to the coordinates I happened to pick, KABC is not blocked and I would expect you to pick up KABC just fine. It should be very strong like the others, so you might be having difficulty due to multipath. You may be able to get this channel simply by moving your antenna around or pointing it in a different direction.

Since there is significant signal blockage in the area, you'll need to provide a more specific location to get more accurate results.

If the coordinates I used are pretty accurate, then I'd say that KTTV, KCOP, and possibly KABC are being blocked by Mt. Harvard. I would NOT change antennas. With this kind of blockage, I don't think you'll do any better with a different antenna. In fact, if you are really deep into the shadow zone, the only way you're likely to get these channels is with a rooftop antenna.

If you were just a couple of miles to the east, west, or south, you'd be out of the shadow and get all the channels, but with your current location, I'd say you're out of luck on a few channels. If you are willing to install a rooftop antenna, then you should be able to manage receiving a few more channels.

Best regards,
Andy

Thanks andy for the quick response.

Rick_R

03-16-07, 01:31 PM

andy.s.lee

03-16-07, 02:29 PM

Thanks for the explanation about Mt. Harvard. I get all digital stations except KCOP which I do not get at all. However digital channels KCBS, KABC, and KTTV on a bad day might break up occasionally.

I previously got KCOP but one October, I believe in 2005, it suddenly stopped coming in. I was told that KCOP at that time moved their transmitter to be co-located with KTTV which is owned by the same company.

I live in a difficult OTA area but I have a chimney mounted Winegard 8200 UHF/VHF antenna with a Winegard 8275 UHF/VHF preamp.

Rick R
If you provide specific coordinates and antenna height (you can send it via private message if you prefer), I can run an analysis for your location as well. Mt. Harvard should only be an issue for people living pretty close to the mountains like around Sierra Madre or Arcadia. You might be faced with a different kind of obstruction. Let me know if you're interested.

Best regards,
Andy

benway

03-16-07, 09:47 PM

looks like ABC has started stretching the 6.30pm evening news, which looks just awful, in my opinion.

Dont they understand that if you wanted to stretch it, you can do it yourself, but you cant unstretch it???

I also find it hard to believe that anyone actually thinks it looks better like that!

If they feel like they must fill the widescreen, why dont they zoom/crop, preserving the original aspect ratio, instead of stretching and having everyone be fat and short?

rant over...

KABC - 818-863-7468

I tried calling, but this is now a fax#

anyone have current contact info for them, please?

Thanks

StephenMSmith

03-16-07, 10:25 PM

narkspud

03-16-07, 11:24 PM

KABC - 818-863-7468

I tried calling, but this is now a fax#

anyone have current contact info for them, please?

Thanks

Maybe we should send them some complaint faxes. Really wide ones.

KABC has never had true 4x3 on 7.1 though. They've been stretching (perhaps unintentionally) to 3x2 for as long as I've had access to HD. But you're right . . . looks like they've joined the nincompoops at KTLA in 14x9 land, and that's gotta be a deliberate act of sabotage by some management buffoon.

I'm deeply opposed to all distortion or cropping of 4x3 TV pictures. Hate it, hate it, hate it. Please, oh TV stations, leave them 4x3 when you upscale them. Or at least give us a true 4x3 option on a subchannel. Jeez.

DSperber

03-17-07, 05:24 AM

looks like ABC has started stretching the 6.30pm evening news, which looks just awful, in my opinion.I noticed that the other day and, like you, cringed! What are they thinking? Do they believe that it looks "good"? That people with short squat fat heads look good?

Tonight I could hardly contain myself, finally getting around to watching "America's Next top Model" from Wednesday night on my TWC DVR. Well first, it started about 7 minutes late because of some stupid basketball game (yes, that really bothers me... just as KTLK radio's preemption of progressive talk radio during basketball and hockey season because of Clippers and Kings games bothers me), so that the end of the show was not recorded. I now have to record/watch the last 10 minutes of Sunday night's rebroadcast.

But the real problem was that just like ABC, KTLA-DT broadcasts 4:3 SD content in 14:9 stretch-o'-vision!!! THIS SHOW WAS UNWATCHABLE! I wonder if Tyra knows the presentation was butchered here in LA like this?

These guys that run the networks, like TNT-HD, KTLA-DT, ABC-DT... do they really not watch the stuff they put on the air? What in the world is wrong with broadcasting in human-friendly 4:3 OAR??? It's not 16:9 content and they know it. Do they honestly believe with their own eyes that 4:3 stretched into 14:9 is good looking???

I am PISSED! I've written an email to the station manager, but who knows if it';; just fall on deaf ears (the same ones that actually put it on the air that way in the first place).

andy.s.lee

03-17-07, 07:33 AM

Would someone mind saving me several hours reading the first 43 pages of this thread and tell me what I should expect as far as OTA HD reception goes for my new condo. It's in Marina del Rey and has facing SW, so I can only see the ocean/marina and directly south. I'm guessing Mt Wilson is on the other side of the building...
See the attached radar plot to see what's "in the air" at Marina Del Rey. Things would be easy if you could put the antenna on the roof. Otherwise, I guess you'll just have to try it and see how "transparent" the building is (to RF energy, that is).

Best regards,
Andy

ldogg29

03-17-07, 01:46 PM

:eek:

CPanther95

03-17-07, 01:49 PM

Threads merged.

benway

03-17-07, 08:47 PM

re ABC stretch

try KABC-TV.MAYOR@abc.com

attn Cheryl Fair / News Director I wrote to her before when their 5.1 sound had no center channel.

or http://abclocal.go.com/kabc/story?section=stationinfo&id=1642694

StephenMSmith

03-18-07, 02:27 AM

See the attached radar plot to see what's "in the air" at Marina Del Rey. Things would be easy if you could put the antenna on the roof. Otherwise, I guess you'll just have to try it and see how "transparent" the building is (to RF energy, that is).

Best regards,
Andy

Well, the roof is not an option. I'm hoping for a repeat of the indoor antenna miracle (for me at least) I got in my current apartment -- I'm completely surrounded by tall buildings and have no clear view of the sky in any direction. Yet I get everything that LA has in OTA HD just fine.

Rick_R

03-19-07, 12:55 PM

If you provide specific coordinates and antenna height (you can send it via private message if you prefer), I can run an analysis for your location as well. Mt. Harvard should only be an issue for people living pretty close to the mountains like around Sierra Madre or Arcadia. You might be faced with a different kind of obstruction. Let me know if you're interested.

Best regards,
Andy
My problem is that directly in my line of sight to 35 mile away Mt Wilson is 2714' Rocky Peak that is 3 miles away. I have a Winegard 8200 UHF/VHF antenna with a Winegard 8275 UHF/VHF preamp. My antenna is 25' above ground level and my zip is 93063.

Rick R

andy.s.lee

03-19-07, 05:04 PM

My problem is that directly in my line of sight to 35 mile away Mt Wilson is 2714' Rocky Peak that is 3 miles away. I have a Winegard 8200 UHF/VHF antenna with a Winegard 8275 UHF/VHF preamp. My antenna is 25' above ground level and my zip is 93063.
Based on the attached map, it looks like some parts of this zip code are shadowed and other parts are not. Using the zip code alone for the basis of a channel receivability analysis might give a false sense of what you can really expect to get. If you would like to evaluate your exact location and see just how "deep" you are in the shadows, I'd need a more precise coordinate. You can send that info via a private message if you want to keep it off the forum.

Best regards,
Andy

jammer13

03-19-07, 11:29 PM

andy.s.lee

03-20-07, 01:58 AM

I'm trying to add some OTA HD to my recent Dish HD upgrade. After reading forum threads for some time and checking antennaweb and Google Earth, I'm a little concerned about reception and which antenna to try first. GE shows a hill a little over 2 miles away that gets to just over 1000' while my house is at around 360'. Antennaweb shows no digital channels for my specific address but about a quarter mile south shows them all. If I put a decent antenna on the current mast it will be about 22' high. Zip is 92821 - cross streets Brea Blvd and Lambert.

I actually tried with current really old antenna and 300-ohm wire - couldn't get any HD channels other than 4.1 which dropped frequently. Any advice or experience with this area appreciated.
Jay,

See attached radar plot for the analysis of your location. Longer bars represent stronger signals. Details about each transmitter is listed in the table to the right.

My interpretation:

- The bad news is that you're definitely in the shadows of the hills above Rowland Heights. If you'll notice in the table under "Path", every single channel is either single or double edge diffracted ("1Edge" or "2Edge") as opposed to line-of-sight. The LOS path for most of the channels (see under "LOS_h") passes about 65 meters over your head! But not to worry... too much...

- Height helps, but there's no point in going to extremes (more expense, more trouble, slight improvement). I usually recommend going with a 10 foot pole on the roof using a chimney or tripod mount since that's about as much height as you can get with minimum effort. If you're able and willing to go higher, that's up to you.

- The semi-good news is that there are still a fair number of channels that should be receivable if you get a high gain antenna (e.g., Channel Master 4228, AntennasDirect XG91, or Televes DAT-75). You'll also want to get a low noise-figure pre-amp (e.g. Winegard AP-4700 or Channel Master 7775) in order to minimize signal loss due to cables and splitters. You'll probably be able to receive everything above -100 dBm (under "Rx_dBm") relatively easily and you may actually be able to receive things down to about -110 dBm, give or take. However, as you get close to the lower limits of the system, there will be less margin for variations and errors (e.g., bad weather, multipath, antenna movement, etc.).

- I don't recall off hand whether any of the current digital channels will be moving to VHF in the future, so perhaps someone else could check on this.

- A quad-shielded RG-6 cable is ideal, but standard double-shielded RG-6 should also work just fine if you include one of the pre-amps above. Having extra shielding only helps if you need additional noise immunity due to nearby RF emissions. If the existing cable is something worse, like RG-59, then it should be replaced. RG-59 is more lossy (although that shouldn't matter with the pre-amp) and is more prone to noise ingress.

Although your situation is a bit tougher than average, I still think that a well installed system will get you a good number of the Mt. Wilson digital channels.

I hope this helps. Good luck!

Best regards,
Andy

Rick_R

03-20-07, 01:19 PM

Based on the attached map, it looks like some parts of this zip code are shadowed and other parts are not. Using the zip code alone for the basis of a channel receivability analysis might give a false sense of what you can really expect to get. If you would like to evaluate your exact location and see just how "deep" you are in the shadows, I'd need a more precise coordinate. You can send that info via a private message if you want to keep it off the forum.

Best regards,
Andy
Andy,

I have analyzed this extensively. However I would be interested in anything you could add.

I have attached your map with the addition of an X where I live. The oval I added is Rocky Peak. The actual peak is at the north end of the oval but there is a ridge that runs the length of the oval. Mt Wilson is 6 degrees south of due east from me. As you can see this is exactly behind the ridge. I am directly in the shadow of this peak. However with my Winegard 8200 and 8275 preamp combined with RG11 I get all channels except channel 13.

From my house I can see that the antenna is exactly pointing at this ridge.

Rick R

DSperber

03-20-07, 05:17 PM

Tonight I could hardly contain myself, finally getting around to watching "America's Next top Model" from Wednesday night on my TWC DVR.

But the real problem was that just like ABC, KTLA-DT broadcasts 4:3 SD content in 14:9 stretch-o'-vision!!! THIS SHOW WAS UNWATCHABLE! I wonder if Tyra knows the presentation was butchered here in LA like this?Had an excellent phone conversation with the tech honcho at KTLA today, who felt my comments about the non-human apparent proportions inherent in 14:9 stretch-o'-vision were very compelling.

He said the decision to broadcast SD in 14:9 was made many years ago (before he was on board), when HD was in its infancy and KTLA was an early technology leader here in LA. But over the years the subject has been brought up for review and has recently met with much stronger internal bias toward reversing that decision and going back to 4:3 within 16:9 to produce "human proportions". As more viewers become tech savvy and HD-knowledgeable, more are like us in reacting negatively to the truly awful look of 14:9. And they don't want to lose us.

So he said I might be surprised that the change may come much sooner than I might have imagined (he brought up the subject again yesterday, in response to the voice mail I'd left him the other day).

Keep your fingers crossed. Now if we can only get KABC to respond as sensibly as KTLA seems to have done we might soon be able to watch both channels without screaming at the tube.

DSperber

03-20-07, 07:36 PM

So he said I might be surprised that the change may come much sooner than I might have imagined (he brought up the subject again yesterday, in response to the voice mail I'd left him the other day).Two hours later I received a call from this gentleman, who told me "IT'S DONE!". Threw the switch!

I shrieked with joy (and amazement, to be perfectly honest), and told him he was a gentleman and a scholar. And I thanked him sincerely.

So, presumably that means no more stretch-o'-vision 14:9 on KTLA-DT.

narkspud

03-20-07, 09:46 PM

Two hours later I received a call from this gentleman, who told me "IT'S DONE!". Threw the switch!

I shrieked with joy (and amazement, to be perfectly honest), and told him he was a gentleman and a scholar. And I thanked him sincerely.

So, presumably that means no more stretch-o'-vision 14:9 on KTLA-DT.

YESSSSSSSSS!! Excellent job, sir. You and he both have my thanks.

OK, time for an all-out assault on KABC. Executives, sponsors, news people, corporate guys, talent, programming suppliers, and anybody else who will listen (or won't). They're the only station in the market that's still screwing things up.

I sent an email to Cheryl Fair, got a generic cut-n-paste response. Hopefully she will take up the cause, but I can't say I'm optimistic just yet.

TonyW79SFV

03-20-07, 10:35 PM

Interesting to note that the two stations that do SD stretch are also the ones to have HD newscasts; others leave 4:3 as OAR and it's standard network procedure to leave it as OAR too, you can tell when the local commercials are running on KABC and KTLA (sometimes).

jammer13

03-20-07, 11:03 PM

Andy,

Great data, thanks for all your effort on this!

I was thinking of something like a Channel Master 4248 (Yagi) to make it a little easier to mount on my current mast which is about 5' high now. I can probably add another 5 foot section on the current mast to handle the bowtie type (4228) antennas if those are obviously better in this situation. I might have to add some more guy wires to the upper section. The XG91 looks interesting instead of the 4248.

Regarding the VHF, I have a list that shows the future channel assignments in LA and only ABC (to be back on channel 7) KCAL (back on channel 9) and KTTV-Fox (channel 11) are supposed to be in VHF. I already get 7 & 11 from my dish so I'd only be out channel 9. I wonder if any of these UHF antennas could pick that up reasonably. I'd hate to add VHF for just one channel basically.

I hadn't checked the RG6 I just wired through the wall over the weekend. I think it's stuff left over from a cable guy a few years ago-don't know the quality. May have to spring for some better stuff if it is something to worry about.

I'll post my progress as I go along. May take some time to get an antenna - don't seem to have any local shops carrying anything that's been recommended.

Jay

kmillard92

03-20-07, 11:55 PM

Hi everybody (i'm new here),

I live in La Mirada, CA...about 22 miles away from Mt. Wilson. I recently got my first HDTV (a Sharp LC-C3742U 720p LCD (http://www.avsforum.com/avs-vb/showthread.php?t=785366&page=1&pp=30) ) which has NTSC/ATSC/QAM tuners. I am looking for an HDTV antenna to go with my new baby. I've heard good things about the Terk HDTVi (http://www.amazon.com/Terk-Technology-HDTVi-Indoor-Antenna/dp/B0001FV36E) antenna...should I get this, or what else would you recommend?

I mainly watch FOX (channel 11) and ABC (channel 7), what should I get to watch these?

(oh yeah it needs to be indoor. i have pretty much all electronics stores around me, and would buy from a trusted online store. under $50 please)

andy.s.lee

03-21-07, 01:15 AM

I have analyzed this extensively. However I would be interested in anything you could add.

I have attached your map with the addition of an X where I live. The oval I added is Rocky Peak. The actual peak is at the north end of the oval but there is a ridge that runs the length of the oval. Mt Wilson is 6 degrees south of due east from me. As you can see this is exactly behind the ridge. I am directly in the shadow of this peak. However with my Winegard 8200 and 8275 preamp combined with RG11 I get all channels except channel 13.

From my house I can see that the antenna is exactly pointing at this ridge.
Since you've definitely done your homework, all I want to say is how impressed I am that you're able pull in so many obstructed channels. It looks like the line-of-sight path for most of the Mt. Wilson channels are more than 200 meters overhead! You should be the inspiration for everyone else who has a challenging OTA situation on their hands. Quite amazing, really.

Best regards,
Andy

andy.s.lee

03-21-07, 01:47 AM

Regarding the VHF, I have a list that shows the future channel assignments in LA and only ABC (to be back on channel 7) KCAL (back on channel 9) and KTTV-Fox (channel 11) are supposed to be in VHF. I already get 7 & 11 from my dish so I'd only be out channel 9. I wonder if any of these UHF antennas could pick that up reasonably. I'd hate to add VHF for just one channel basically.
Since these are all high VHF, you might consider adding the Winegard YA-1713 and then use a Winegard 2870 pre-amp to handle both VHF and UHF. The OTA service might include subchannels that your dish service doesn't carry, plus there might be some quality degradation due to the extra recompression step needed to get the OTA feed into the satellite stream. Just food for thought.

BTW, if you decide to go ahead with the dual antenna setup, it's theoretically better to put the UHF antenna on top and the VHF on the bottom since lower frequencies can diffract ("bend") further than higher frequencies. Although the difference is probably to small to actually make any practical difference, it's just what the engineer in me would do.

I hadn't checked the RG6 I just wired through the wall over the weekend. I think it's stuff left over from a cable guy a few years ago-don't know the quality. May have to spring for some better stuff if it is something to worry about.
If the cable is already RG-6, I wouldn't worry about it too much. Even "standard" RG-6 should have double layer foil shielding and fairly low loss. With a pre-amp in place, you should not have any problems. Just make sure the cable is not RG-59 or something else.

Best regards,
Andy

benway

03-21-07, 11:54 AM

thats great -- KABC next!

Two hours later I received a call from this gentleman, who told me "IT'S DONE!". Threw the switch!

I shrieked with joy (and amazement, to be perfectly honest), and told him he was a gentleman and a scholar. And I thanked him sincerely.

So, presumably that means no more stretch-o'-vision 14:9 on KTLA-DT.

DSperber

03-21-07, 12:42 PM

thats great -- KABC next!Boy, I was browsing KTLA-DT last night and am still getting used to seeing "Friends" in 4:3 (no more "Jabba the Hut"), Clippers highlights in 4:3, etc. Very different than 14:9, but it's watchable again and I'm thrilled to have been able to persuade them to do this so quickly. I'm guessing they'd been considering this action for a while, and my call simply pushed them off the dime.

I just got off the phone with the KABC counterpart of my KTLA contact, and he too will get back to me later today or tomorrow. I added this latest news, about KTLA throwing the switch yesterday and reverting to true 4:3 for SD... thus now leaving KABC-DT as the only remaining major network "villain" in the LA area who's still stretching SD into 14:9. I'm hoping this will have some impact, and that we will see KABC-DT also start presenting SD in true 4:3.

Of course 4:3 looks different than 16:9, which might also have a side benefit of encouraging both networks to provide more true 16:9 HD (or at least encourage producers to provide 16:9 true HD content instead of 4:3 SD) where they currently are still showing something in 4:3 SD. I realize this does not apply to syndicated SD shows, especially old series like "Friends". But hopefully they will now appreciate that there truly are HD watchers/lovers on the other side of the tube, who want as much 16:9 true HD as they can be fed.

Keep your fingers crossed for KABC-DT to also consider my arguments "compelling", and to make the same change as KTLA-DT has now made.

And that would leave TNT-HD as the major cable network guilty of the same crime.

Rick_R

03-21-07, 12:52 PM

Andy,

Just one more interesting comment.

There is a pass through the hills about 20 to 25 degrees south of due east. When I point the antenna directly at Mt Wilson at 6 degrees south of due east I get breakups. I attributred this to multi path from the direct signal and the signal through the pass. I now aim the antenna at about 1 to 2 degrees north of due east. This has the effect of rejecting the signal through the pass but still gets the direct signal fine. This gives me the best signal.

Rick R

StephenMSmith

03-21-07, 01:56 PM

twelvepbrs

03-21-07, 02:10 PM

Wow, nice work on fixing the stretch-o-vision. Now, let's get the friggin KNBC's friggin DD audio flag set properly so I don't have to switch to analog audio to get the dialog to eminate from the center channel.

For Conan at least. I don't care about the rest of KNBC's programming.
It wouldn't hurt if NBC's sports didnt look so sh*tty in HD, i guess it doesnt really matter since i hate notre dame but still...it IS fun to watch them lose, someday i'll try to cap one of their HD sports broadcasts, i have a feeling it's pretty low

kmillard92

03-21-07, 02:42 PM

twelvepbrs

03-21-07, 03:20 PM

can someone help me please, or at least point me in th right direction to an article or something? thanks :p
not to try to subvert the OTA route, but if you have any kind of cable service at all, you could try plugging the cable directly into your tv and see if you get the local channels in HD since they should be unencrypted (although it's a crapshoot as to what's available depending on your area), and after your tv does a cable channel scan it could take at least several minutes to figure out where the channels are located #-wise; just a thought since this could be a quick/temporary fix until you get your OTA situation straigthened out

csrini1

03-21-07, 04:58 PM

can someone help me please, or at least point me in th right direction to an article or something? thanks :p

TErk is fine, but i got myself a Philips PHDTV3 Indoor HDTV UHF/VHF Powered Antenna, and i don't have any regrets yet. This was able to catch 33 channels(most of them i don't watch or understand, i do get cbs/abc/nbc/foc/ktla/pbs etc.

kmillard92

03-21-07, 07:11 PM

TErk is fine, but i got myself a Philips PHDTV3 Indoor HDTV UHF/VHF Powered Antenna, and i don't have any regrets yet. This was able to catch 33 channels(most of them i don't watch or understand, i do get cbs/abc/nbc/foc/ktla/pbs etc.

I got this Philips VHF/UHF/FM/HDTV antenna (http://www.circuitcity.com/ssm/Philips-Dual-Passive-Indoor-Antenna-SDV2270/sem/rpsm/oid/158310/rpem/ccd/productDetail.do#tabs) for free ($20 normally) because I got them to throw it in with my TV stand. Maybe I need to rescan for channels, but I'm not getting any 2-11 DTV channels (except for 5.1 & 5.5) , but the analog ones are coming in ok. I'm getting alot of DTV from the Hispanic channels...suggestions?

EDIT: After rescanning, I am now receiving the channel 2, 4, 5 (the music channel is nice), 9, and 11 DTV channels, but still not channel 7. Anything I can do? (man, more people need to shoot stuff in HD.)

Double EDIT: I'm now getting Channel 7 with around 50% signal, but it keeps dropping. (Man, Ellen Leyva needs a facelift :D )

holl_ands

03-21-07, 08:55 PM

twelvepbrs

03-21-07, 09:44 PM

i picked up another digital-tuner (HDHomerun) and it has more signal measurements than the "Signal Strength" indicator on my tv (which isnt really signal strength, not sure what it is) the HDHomerun reports "Signal Strength" "Signal Quality" and "Symbol Quality" if anyone knows exactly what these mean i'd really appreciate it (although i'm pretty sure signal strength is self-explanatory) since i have a ton of signal according to the map andy posted, and the software indicates 90-100% for every channel, i'm still having a lot of problems tuning, the "signal quality" for everything is 50% or below, i'm guessing that this is due to multipath interference

coyoteaz

03-21-07, 09:51 PM

Wow, nice work on fixing the stretch-o-vision. Now, let's get the friggin KNBC's friggin DD audio flag set properly so I don't have to switch to analog audio to get the dialog to eminate from the center channel.

For Conan at least. I don't care about the rest of KNBC's programming.
The flags in the metadata NBC sends out are always set to 5.1 and have been since the Olympics, so KNBC is not at fault for following what is given to them. Setting the encoder to 2.0 would require someone to manually make the change back and forth, which would cause far worse problems when they forget to set it back and the entire primetime lineup is broadcast without dialog.

StephenMSmith

03-21-07, 10:42 PM

The flags in the metadata NBC sends out are always set to 5.1 and have been since the Olympics, so KNBC is not at fault for following what is given to them. Setting the encoder to 2.0 would require someone to manually make the change back and forth, which would cause far worse problems when they forget to set it back and the entire primetime lineup is broadcast without dialog.

Yeah, KABC/ABC is the same way -- always reads as 5.1 in my decoder but it doesn't always get decoded into L+R channels only like Conan, etc. Not sure why that is, unless the audio is actually mono and therefore decoded into 5.1's center channel only.

Regardless, then how does CBS/KCBS do it? They have no issues =getting the proper flag set correctly at all, and even switch to 2.0 for the commercials in the middle of a 5.1 broadcast. I'm just looking for KNBC (or NBC) to just set the correct flag for the broadcast, ie. Conan is recorded w/2 channels -- stop broadcasting it w/the incorrect 5.1 flag set.

Letterman had this very same problem back when I first got HD. I emailed KCBS about it and got someone who acknowledged the issue and fixed it right then. HD Letterman has been correctly flagged as 2.0 ever since. So I know it can be done! I emailed him back asking if he was KCBS or CBS but never got a response. I was just happy to have Letterman's voice eminating from his mouse (ie. my center channel) instead of simultaneously echoing out of my left and right walls.

benway

03-22-07, 12:17 AM

yes, fingers crossed for KABC

however, it now appears that the geniuses at KNBC are using stetch o vision on their 7pm access hollywood/extra shows

do you know anyone over there? it amazes me that anyone can think that stretch o vision is a good idea.

as regards the 5.1 NBC issues-- Scrubs is never flagged correctly but the shows either side of it are.

Deal or no deal-- their biggest show is not flagged correctly either.

as someone pointed out CBS gets it right. so does Fox. and PBS. and 13 and KTLA

anyway, thanks for your efforts-- much appreciated

Boy, I was browsing KTLA-DT last night and am still getting used to seeing "Friends" in 4:3 (no more "Jabba the Hut"), Clippers highlights in 4:3, etc. Very different than 14:9, but it's watchable again and I'm thrilled to have been able to persuade them to do this so quickly. I'm guessing they'd been considering this action for a while, and my call simply pushed them off the dime.

I just got off the phone with the KABC counterpart of my KTLA contact, and he too will get back to me later today or tomorrow. I added this latest news, about KTLA throwing the switch yesterday and reverting to true 4:3 for SD... thus now leaving KABC-DT as the only remaining major network "villain" in the LA area who's still stretching SD into 14:9. I'm hoping this will have some impact, and that we will see KABC-DT also start presenting SD in true 4:3.

Of course 4:3 looks different than 16:9, which might also have a side benefit of encouraging both networks to provide more true 16:9 HD (or at least encourage producers to provide 16:9 true HD content instead of 4:3 SD) where they currently are still showing something in 4:3 SD. I realize this does not apply to syndicated SD shows, especially old series like "Friends". But hopefully they will now appreciate that there truly are HD watchers/lovers on the other side of the tube, who want as much 16:9 true HD as they can be fed.

Keep your fingers crossed for KABC-DT to also consider my arguments "compelling", and to make the same change as KTLA-DT has now made.

And that would leave TNT-HD as the major cable network guilty of the same crime.

jammer13

03-22-07, 12:28 AM

Since these are all high VHF, you might consider adding the Winegard YA-1713 and then use a Winegard 2870 pre-amp to handle both VHF and UHF. The OTA service might include subchannels that your dish service doesn't carry, plus there might be some quality degradation due to the extra recompression step needed to get the OTA feed into the satellite stream. Just food for thought.

BTW, if you decide to go ahead with the dual antenna setup, it's theoretically better to put the UHF antenna on top and the VHF on the bottom since lower frequencies can diffract ("bend") further than higher frequencies. Although the difference is probably to small to actually make any practical difference, it's just what the engineer in me would do.

The YA-1713 is probably a good idea. What I might do is try the 91XG on my current mast and if that works pray like heck that E* adds channel 9 as high def at some point. You're right about the compression issue of course but trade-offs may have to be made. I have a metal-tile roof which I'm very leary about poking too many holes in it (it's also hard to walk on) so I'm trying to keep my current mast setup even though it's pretty old and worn(but it is stable). If the 91XG doesn't work on the shorter mast, I'll have to figure a way to add another 5' section which would probably leave room for the VHF antenna or abandon the current mast and try maybe a vent pipe mount with guy wires or some such.

Jay

narkspud

03-22-07, 12:50 AM

>>it now appears that the geniuses at KNBC are using stetch o vision on their 7pm access hollywood/extra shows<<

Like herding cats, ain't it.

wolfeinstein

03-22-07, 02:24 AM

twelvepbrs

03-22-07, 03:06 AM

Hi All!

I live in aliso viejo 92656 and trying to get hd OTA which antenna you guys think i should get?
i just bought a condo i have an upstairs neighbor so on the roof i dont think i can instal it!

heres some pic that faces the 322 degrees where my antenna should face!
i just need some input on the type of antenna i should get!
thx

Did you ask your neighbor if you could put an antenna up there? i'm assuming the neighbor is a crotchety old woman with a black and white set with rabbit ears, but otherwise they might be interested getting hooked in to an antenna on the roof, or at least will to let you put it up there for a case of beer (or a keg if they are paranoid)

TonyW79SFV

03-22-07, 03:08 AM

Wow, KNBC for the longest time ran 4:3 OAR. All of a sudden we successfully got KTLA to stop stretchovision only to have KNBC start it.

DSperber

03-22-07, 06:47 AM

however, it now appears that the geniuses at KNBC are using stetch o vision on their 7pm access hollywood/extra shows

do you know anyone over there? it amazes me that anyone can think that stretch o vision is a good idea.As a matter of fact, I do. I had a very productive period of conversations with the guy back during the Olympics when the audio levels on KNBC-DT were absolutely awful and the lip-sync problems were horrible! Could hardly hear anything, not to mention the false reporting of DD5.1 in the metadata.

Ultimately my pestering had at least some effect, as they (or perhaps the network out of NY) increased the audio level significantly after a few days of many complaints I would guess (although it's still the lowest level of any network in town). And it took them a long time to resolve the lip-sync problems (especially on Leno), but things finally got fixed and I'm sure my interactions with him had lots to do with it.

Nevertheless, I did develop a good rapport with the gentleman, and he was very willing to talk with me about many technical subjects. He knows about AVS Forum.

I didn't know that they had started using stretch-o-vision lately, because I never watch any show that's not HD. I actually watch very little on NBC (other than Leno, and "Las Vegas") and it's always HD.

I'll give him a call tomorrow and see if he can tell me why they did it. I'll also let him know that KTLA has stopped doing it and is now broadcasting SD in 4:3.

DSperber

03-22-07, 08:36 AM

Wow, KNBC for the longest time ran 4:3 OAR. All of a sudden we successfully got KTLA to stop stretchovision only to have KNBC start it.Happened to catch the late rebroadcast of the 11PM news, and now early this morning the morning news.

While not 16:9, this is certainly not 4:3 and it definitely is NOT 14:9 distorted stretch-o-vision. Looks like a wide frame (wider than 4:3) , and very high quality... just not 16:9 HD. People still have normal proportions and it looks very high quality... though not HD, and the frame is definitely much wider than 4:3.

Now this may not be what they're doing with Extra and Access Hollywood and other SD programs, but the news looks very good. I would not complain about this.

I'll check in tonight at 7PM to see what's going on there.

narkspud

03-22-07, 09:52 AM

While not 16:9, this is certainly not 4:3 and it definitely is NOT 14:9 distorted stretch-o-vision. Looks like a wide frame (wider than 4:3) , and very high quality... just not 16:9 HD. People still have normal proportions and it looks very high quality... though not HD, and the frame is definitely much wider than 4:3.

???

I'm looking at the news right now. It's definitely sharper than KABC's SD upconvert, but outside that, it looks like classic stretch-o-vision to me. It's very obvious in the NBC logo - the peacock looks mooshed.

Perhaps they're experimenting with different configurations?

DSperber

03-22-07, 03:13 PM

I'm looking at the news right now. It's definitely sharper than KABC's SD upconvert, but outside that, it looks like classic stretch-o-vision to me. It's very obvious in the NBC logo - the peacock looks mooshed.Ok, my mistake. I must have been very tired and the sharpness of the picture distracted me.

Yes, you are correct. They have indeed decided (just within the past two days) to move to 14:9 SD, per facts learned from my just completed phone call with the tech honcho at KNBC. He laughed his ass off that I was calling him just a day after they'd made the decision to go this route, and my call was not the first on this subject.

The decision is not cast in stone, but for now they are reacting to viewer's comments that "they don't want to see the black bars on the left and right". Of course the cheapie solution is to stretch the 4:3 picture instead of investing in an HD news set. And of course this is the "only solution" for SD syndicated shows, etc.,

My argument is that if a viewer wants to "zoom" or "stretch" the picture he/she receives, that should be his/her decision using his/her HDTV equipment. But other viewers who prefer to watch 4:3 as 4:3 lose that option if the station stretches what it sends out.

And he fully understands and agrees, and also said the decision was not entirely his to make, nor did he necessarily agree with the outcome that was decided.

As part of their "evidence supporting this decision" was the fact that KTLA was doing the same thing. I told him that I had just in the past two days managed to prevail in persuading his counterpart at KTLA to throw the switch and go back to true unstretched 4:3 for SD, and he again laughed his ass off. He was going to send out an email to that effect before he went to lunch... since this was indeed very interesting and provocative news.

Anyway, he gave me the email address of the News Director (Robert Long) who would be another "receptive ear" at KNBC. If enough viewers write or call and complain about this "Jabba the Hut" new look to SD on KNBC-DT (news or other syndicated SD shows, like Extra and Access Hollywood) it could certainly swing them to reverse this very recent technical decision.

Again, it's unfair that people with old equipment that cannot "zoom" (if that's what they prefer to look at or because they want to prevent "screen burn", for whatever reason) now prevent those of us who can "zoom" or prefer to watch 4:3 as 4:3 from having maximum flexibility. And he realizes that, and agrees.

But for now, it does look grim. I told him my solution was simply to watch 4:3 SD on my four other 4:3 SD televisions around the house, which really is perfectly acceptable to me. I only watch serious 16:9 HD content on my HDTV. I almost never opt to watch SD content on my HDTV, unless I happen to be watching "live" a channel on the hour or half-hour when an SD show comes on. In fact, with a DVR I virtually NEVER watch anything "live" anyway.

narkspud

03-22-07, 09:49 PM

Yes, you are correct. They have indeed decided (just within the past two days) to move to 14:9 SD, per facts learned from my just completed phone call with the tech honcho at KNBC.

I don't think you were entirely wrong. It looks like they're hedging their bets by also shaving off a good chunk at the top and bottom. Looks very claustrophobic, and some title-safe stuff in the ads is now going right off the edges. The sponsors are going to love this. ('Specially if somebody tells 'em. ;) )

I bet they're feeling HD envy, and the complaints are from some of their dumber newscast viewers who don't get why KTLA and KABC's newscasts don't have black bars, but KNBC's does. Observation: they still do, they're just not as big. The worst of both worlds. Grrrrrrrr.

Rick_R

03-23-07, 12:50 PM

Anyway, he gave me the email address of the News Director (Robert Long) who would be another "receptive ear" at KNBC. If enough viewers write or call and complain about this "Jabba the Hut" new look to SD on KNBC-DT (news or other syndicated SD shows, like Extra and Access Hollywood) it could certainly swing them to reverse this very recent technical decision.

Do ypu have an email address or phone number I can call to complain?

I hate stretch and will not watch it. If I must watch a stretched show I switch to the SD channel.

I was thinking of watching the Miss Universe USA pagent on KNBC tonight. However if all the contestants will be fat because of the stretch I certainly will not watch. I am asssuming it will not be in HD.

Rick R

benway

03-23-07, 03:01 PM

yes I would like to contact NBC too and tell them about the 5.1 issues.

also, I think "zoom" or auto stretch " is available on both the HDTV receiver and the display.

so most should have this if they want it.

thanks

coyoteaz

03-23-07, 03:15 PM

Yeah, KABC/ABC is the same way -- always reads as 5.1 in my decoder but it doesn't always get decoded into L+R channels only like Conan, etc. Not sure why that is, unless the audio is actually mono and therefore decoded into 5.1's center channel only. If KABC is running full-time 5.1, they probably have a device that upmixes all the 2.0 to 5.1 and passes through 5.1 untouched. A number of stations have these devices, primarily to keep the pretty 5.1 light lit on people's receivers, but also for certain older bitstream encoders that don't have the ability to switch on the fly between 2.0 and 5.1. Also, ABC doesn't send out any metadata with their audio like NBC and CBS do because of how they distribute it, so it's entirely up to the stations how they want to set the audio.
Regardless, then how does CBS/KCBS do it? They have no issues =getting the proper flag set correctly at all, and even switch to 2.0 for the commercials in the middle of a 5.1 broadcast. I'm just looking for KNBC (or NBC) to just set the correct flag for the broadcast, ie. Conan is recorded w/2 channels -- stop broadcasting it w/the incorrect 5.1 flag set.

Letterman had this very same problem back when I first got HD. I emailed KCBS about it and got someone who acknowledged the issue and fixed it right then. HD Letterman has been correctly flagged as 2.0 ever since. So I know it can be done! I emailed him back asking if he was KCBS or CBS but never got a response. I was just happy to have Letterman's voice eminating from his mouse (ie. my center channel) instead of simultaneously echoing out of my left and right walls.CBS and NBC send out metadata with their audio, which can be directed to the audio encoder to tell it how to set the channels (2.0, 5.1, etc), bitrate, and mix levels. NBC hardwired theirs to 5.1 for the Olympics because a number of stations weren't switching properly and were losing the center channel dialog. CBS sets theirs properly, so any stations which follow it will almost always have correct audio. Incidentally, CBS also handles distribution for CW, so their audio system works in the same fashion, though few of the shows on CW are 5.1.

Many viewers and station engineers have contacted NBC to complain, but they just don't care.

twelvepbrs

03-23-07, 04:43 PM

If KABC is running full-time 5.1, they probably have a device that upmixes all the 2.0 to 5.1 and passes through 5.1 untouched. A number of stations have these devices, primarily to keep the pretty 5.1 light lit on people's receivers, but also for certain older bitstream encoders that don't have the ability to switch on the fly between 2.0 and 5.1. Also, ABC doesn't send out any metadata with their audio like NBC and CBS do because of how they distribute it, so it's entirely up to the stations how they want to set the audio.
CBS and NBC send out metadata with their audio, which can be directed to the audio encoder to tell it how to set the channels (2.0, 5.1, etc), bitrate, and mix levels. NBC hardwired theirs to 5.1 for the Olympics because a number of stations weren't switching properly and were losing the center channel dialog. CBS sets theirs properly, so any stations which follow it will almost always have correct audio. Incidentally, CBS also handles distribution for CW, so their audio system works in the same fashion, though few of the shows on CW are 5.1.

Many viewers and station engineers have contacted NBC to complain, but they just don't care.
CBS handles the CW? don't they also have KCAL? so KCBS is tied into half of the local HD's that are worth watching

DSperber

03-23-07, 05:46 PM

Do you have an email address or phone number I can call to complain?The tech fellow is Steve Colley: 818 840 3375. He's very nice and smart, and actually answers the phone. I'm sure he'd be interested in hearing comments from tech-savvy people such as our group.

But I don't want to abuse my access to him by having the whole of AVS LA calling him to moan. However I'm sure a few well verbalized "viewer comments" would be much appreciated by him, although he's very much on our side on a lot of this discussion.

He gave me News Director Robert Long's email address: Robert.Long@nbcuni.com, which he believed was displayed on a crawl every Friday afternoon (for viewer comments).

So let's be thoughtful and non-hostile in use of this "inside contact information". Again, he's a very nice and smart guy, and absolutely knows his tech stuff.

DSperber

03-23-07, 05:51 PM

yes I would like to contact NBC too and tell them about the 5.1 issues.This decision was a corporate one out of NY, and KNBC out here cannot influence this. I've had this discussion with him extensively, especially back during the Winter Olympics when they first went to DD5.1 "falsely".

I told him yesterday that other local stations (e.g. KCBS) manage to make the switch from DD5.1 to DD2.0 during commercials with no problem, and he's aware of that. He thinks it's actually a cost issue, with proper investment in new hardware/software the correct solution.

He did say that I might be surprised to find this one resolved sooner rather than later (as if some big decision might be pending), but didn't get any more specific.

However he is completely familiar with the issue, and the problem, and the effect, and apparently has no way of changing the NY-corporate decision until infrastructure is changed.

coyoteaz

03-23-07, 07:16 PM

CBS handles the CW? don't they also have KCAL? so KCBS is tied into half of the local HD's that are worth watchingCBS is the C in CW. KTLA is owned by Tribune, so CBS has no direct involvement besides providing 2 hours per night of network programming. Tribune ended up being the odd man out in the merger between WB (owned by Warner and Tribune) and UPN (owned by CBS), though they still own the CW affiliates in 6 of the top 10 markets. KCAL is owned and operated by CBS.

coyoteaz

03-23-07, 07:27 PM

This decision was a corporate one out of NY, and KNBC out here cannot influence this. I've had this discussion with him extensively, especially back during the Winter Olympics when they first went to DD5.1 "falsely".

I told him yesterday that other local stations (e.g. KCBS) manage to make the switch from DD5.1 to DD2.0 during commercials with no problem, and he's aware of that. He thinks it's actually a cost issue, with proper investment in new hardware/software the correct solution.

He did say that I might be surprised to find this one resolved sooner rather than later (as if some big decision might be pending), but didn't get any more specific.

However he is completely familiar with the issue, and the problem, and the effect, and apparently has no way of changing the NY-corporate decision until infrastructure is changed.NBC was the one of the first networks to do DD5.1 audio. They started doing it before the advent of Dolby E. Basically, NBC distributes 4 pairs of stereo audio (L/R, SL/SR, C/S, and Lt/Rt) which each local station must take and combine to make either 2.0 or 5.1 audio. They also provide metadata in their stream to tell the station to go with 5.1 or 2.0. 2.0 should come from Lt/Rt (t standing for total) which is effectively ProLogic or Dolby Surround. 5.1 should come from the other 3 pairs. Problems occur primarly when the station is running in 2.0 using L/R instead of Lt/Rt which gives no dialog, or when running in 5.1 with audio only in L/R (Conan, Leno, etc.). Further problems can occur if the station uses Lt/Rt instead of L/R on a 5.1 mix, which results in the dialog being on all 3 channels, and usually enough out of sync to sound like it was recorded in a bathroom or tunnel. CBS and CW avoid this by using the newer Dolby E standard which allows them to send the audio out encoded into 1 stereo pair, which a decoder then splits out into the discrete channels. Basically, NBC's system is hacked together with duct tape and bandaids since no better solution existed when they started doing 5.1. The only way to fix it would be for every NBC affiliate to purchase Dolby E decoders and for NBC to start distributing in this format. NBC has already shown that they really don't care to spend the money to provide a top quality broadcast (use of Ku band for distribution, heavy emphasis on cheap reality shows rather than moving to HD, etc.) so don't count on this happening any time soon.

narkspud

03-23-07, 09:17 PM

Have you gotten really, really mad today? No? Well, I sure did:

From KNBC spokesperson Erin Dittman (Erin.Dittman@nbcuni.com):

>>Thank you for your recent email and for expressing your viewpoint. We
are moving towards our goal of full HD transmission and a 16:9 format,
but in the interim, have received numerous requests to provide a larger
screen format. The larger 14:9 format is a temporary solution while we
endeavor to complete our HD plans. You might be interested to know that
NBC "Nightly News with Brian Williams" will begin broadcasting in HD
beginning on Monday, March 26th. We hope you will continue to watch
Channel Four and thank you for your patience during this time of
transition.<<

In the interim? Temporary solution? I think a deluge of emailed complaints would be in order.

holl_ands

03-24-07, 01:58 AM

NBC was the one of the first networks to do DD5.1 audio. They started doing it before the advent of Dolby E. Basically, NBC distributes 4 pairs of stereo audio (L/R, SL/SR, C/S, and Lt/Rt) which each local station must take and combine to make either 2.0 or 5.1 audio. They also provide metadata in their stream to tell the station to go with 5.1 or 2.0. 2.0 should come from Lt/Rt (t standing for total) which is effectively ProLogic or Dolby Surround. 5.1 should come from the other 3 pairs. Problems occur primarly when the station is running in 2.0 using L/R instead of Lt/Rt which gives no dialog, or when running in 5.1 with audio only in L/R (Conan, Leno, etc.). Further problems can occur if the station uses Lt/Rt instead of L/R on a 5.1 mix, which results in the dialog being on all 3 channels, and usually enough out of sync to sound like it was recorded in a bathroom or tunnel. CBS and CW avoid this by using the newer Dolby E standard which allows them to send the audio out encoded into 1 stereo pair, which a decoder then splits out into the discrete channels. Basically, NBC's system is hacked together with duct tape and bandaids since no better solution existed when they started doing 5.1. The only way to fix it would be for every NBC affiliate to purchase Dolby E decoders and for NBC to start distributing in this format. NBC has already shown that they really don't care to spend the money to provide a top quality broadcast (use of Ku band for distribution, heavy emphasis on cheap reality shows rather than moving to HD, etc.) so don't count on this happening any time soon.
Where's the chewing gum?????
Looks pretty straight forward:
http://www.dolby.com/professional/pro_audio_engineering/5_1_implementations/

StephenMSmith

03-24-07, 03:27 AM

NBC was the one of the first networks to do DD5.1 audio. They started doing it before the advent of Dolby E. Basically, NBC distributes 4 pairs of stereo audio (L/R, SL/SR, C/S, and Lt/Rt) which each local station must take and combine to make either 2.0 or 5.1 audio. They also provide metadata in their stream to tell the station to go with 5.1 or 2.0. 2.0 should come from Lt/Rt (t standing for total) which is effectively ProLogic or Dolby Surround. 5.1 should come from the other 3 pairs. Problems occur primarly when the station is running in 2.0 using L/R instead of Lt/Rt which gives no dialog, or when running in 5.1 with audio only in L/R (Conan, Leno, etc.). Further problems can occur if the station uses Lt/Rt instead of L/R on a 5.1 mix, which results in the dialog being on all 3 channels, and usually enough out of sync to sound like it was recorded in a bathroom or tunnel. CBS and CW avoid this by using the newer Dolby E standard which allows them to send the audio out encoded into 1 stereo pair, which a decoder then splits out into the discrete channels. Basically, NBC's system is hacked together with duct tape and bandaids since no better solution existed when they started doing 5.1. The only way to fix it would be for every NBC affiliate to purchase Dolby E decoders and for NBC to start distributing in this format. NBC has already shown that they really don't care to spend the money to provide a top quality broadcast (use of Ku band for distribution, heavy emphasis on cheap reality shows rather than moving to HD, etc.) so don't count on this happening any time soon.

Thanks, This explains quite a bit, especially for KABC and the odd channels that active for some stereo shows but not others while the DD flag is always 5.1. But I'm a still little confused...

Using Conan as an example: if NBC is sending out the 4 pairs of stereo audio to their affiliates, then isn't KNBC, the local affiliate, the one screwing it up by using L/R instead of Lt/Rt? Does this 5.1 w/L&R channels only problem occur for every HD local broadcast of Conan in the US?

WeHoMyke

03-24-07, 08:43 PM

I don't think you were entirely wrong. It looks like they're hedging their bets by also shaving off a good chunk at the top and bottom. Looks very claustrophobic, and some title-safe stuff in the ads is now going right off the edges. The sponsors are going to love this. ('Specially if somebody tells 'em. ;) )

Looks like they are mainly shaving off the top. You can really tell during the local news. They really need to adjust their graphics. :rolleyes:

http://img175.imageshack.us/img175/6706/0324h17m25ch93502nbc4hdgr4.jpg

coyoteaz

03-25-07, 03:00 AM

Where's the chewing gum?????Holding together the wacky Ku distribution scheme NBC decided to go with. A distribution system subject to rain fade? Nah, that won't cause any problems...
Thanks, This explains quite a bit, especially for KABC and the odd channels that active for some stereo shows but not others while the DD flag is always 5.1. But I'm a still little confused...

Using Conan as an example: if NBC is sending out the 4 pairs of stereo audio to their affiliates, then isn't KNBC, the local affiliate, the one screwing it up by using L/R instead of Lt/Rt? Does this 5.1 w/L&R channels only problem occur for every HD local broadcast of Conan in the US?NBC sends out information with their broadcast which tells the stations "this is 5.1" or "this is 2.0". Unfortunately, NBC no longer sets this information properly; they are always saying "this is 5.1". KNBC's encoder complies and maps the 6 channels into the appropriate places, even though C, S, SL, and SR contain silence. The station would need some sort of manual override to go to 2.0 mode from L/R or Lt/Rt (which should be identical in a 2.0 show). Anything that isn't fully automated is subject to people fouling it up, so KNBC takes the safe path and follows what NBC says. I don't think there is any fault to be found with KNBC on the issue as they would likely end up with far worse problems if they tried to work around NBC's flaws.

TonyW79SFV

03-25-07, 06:39 AM

It seems KABC has another syndicated show in HD other than Jeopardy and Wheel. I'm checking what's on TV now at 3am and KABC is showing some show called "Comics Unleashed with Byron Allen". I'm not familiar with the show, but was surprised to see something HD and non-network in the middle of the night.

mikemikeb

03-25-07, 10:15 AM

A distribution system subject to rain fade? Nah, that won't cause any problems...Well, um, perhaps stations could use a really giant satellite dish. Yeah, that's it!

blazera

03-26-07, 02:33 AM

Is it me, or has KABC adopted the "zoom and crop" method of doing 14:9 that KNBC started last week? I compared 7-1 to the analog ch. 7 signal, and it sure looks that way.

narkspud

03-26-07, 09:27 AM

It's a conspiracy.

benway

03-27-07, 03:37 PM

I emailed both those NBC people and had no reply.

Have you gotten really, really mad today? No? Well, I sure did:

From KNBC spokesperson Erin Dittman (Erin.Dittman@nbcuni.com):

>>Thank you for your recent email and for expressing your viewpoint. We
are moving towards our goal of full HD transmission and a 16:9 format,
but in the interim, have received numerous requests to provide a larger
screen format. The larger 14:9 format is a temporary solution while we
endeavor to complete our HD plans. You might be interested to know that
NBC "Nightly News with Brian Williams" will begin broadcasting in HD
beginning on Monday, March 26th. We hope you will continue to watch
Channel Four and thank you for your patience during this time of
transition.<<

In the interim? Temporary solution? I think a deluge of emailed complaints would be in order.

narkspud

03-27-07, 08:44 PM

Looking at KNBC's newscast right now. I see 4:3. Can it be that screaming bloody murder actually helps?

If so, thank you, KNBC.

WeHoMyke

03-27-07, 09:10 PM

Looking at KNBC's newscast right now. I see 4:3. Can it be that screaming bloody murder actually helps?

If so, thank you, KNBC.

Hooray!! I'm watching the 6pm news and it is back to 4:3

http://img292.imageshack.us/img292/8130/0327h18m08ch93502nbc4hdlj5.jpg

WeHoMyke

03-27-07, 09:13 PM

http://www.broadcastingcable.com/article/CA6427588.html?display=Search+Results&text=kcbs

Two CBS-owned stations in Los Angeles are in the final stages of a move to a new state-of-the-art digital broadcast center, joining the growing legion of broadcasters doing high-definition news. KCBS executives have relocated their offices to the CBS Studio Center lot in Studio City, around eight miles to the northwest of the current site on Sunset Boulevard. The news anchors and teams have already begun rehearsals, and everyone's shooting for an April 21 start date for high-definition news at KCBS and sister station KCAL.

The new site is a massive 140,000- square-foot structure, featuring the Jerry Dunphy Newsroom (named for the legendary Los Angeles anchor), and a pair of 5,000-square-foot sound stages for KCBS and KCAL, a CBS-owned independent station. The lot is rich in television history; KCBS executives say vintage programs Gunsmoke and Leave It to Beaver—and, more recently, CSI: New York and Big Brother—were shot there. ...

TheRock

03-27-07, 09:35 PM

Very nice. I was really upset to see NBC go to stretch-o-vision. Its very cool to learn there are some Executives who still care about viewers. I was about to contact them later today. Nice to see that I wont have to. Thanks guys.

Now if only CBS could be convinced to turn off there damn CCI settings. :(

narkspud

03-27-07, 10:03 PM

Now if only CBS could be convinced to turn off there damn CCI settings. :(

I'll be writing to the folks I bothered at KNBC to thank them profusely. BUT . . .

We still have one buncha local weasels transmitting in Distort-O-Rama. Any insiders care to suggest some good contacts over at KABC? We're soooooo close . . . . . . .

Rick_R

03-28-07, 12:46 PM

Thank you, thank you, thank you KNBC.

Only KABC left.

Rick R

DSperber

03-28-07, 01:30 PM

Thank you, thank you, thank you KNBC.Just got off the phone with my KNBC contact, to thank him for reverting back from stretch-o-vision.

He said "well, in this case the voice of the people was heard". I believe my/our comments conveyed to him a few days ago right after KTLA had gone from 14:9 back to 4:3 made their executive re-think their decision. They'd been having this discussion about how to present up-converted SD on the HD channel for several years and last week's experiment apparently was voted down after just a week's trial. The fact that they didn't really want to do the work on the graphics at the top and bottom of the screen which were getting cut off with the new presentation I'm sure also contributed to their decision to back out.

I'm guessing they must have had more input than just mine, from other AVS members as well as "civilian" viewers who called or wrote in to complain.

Anyway, only KABC remains.

TheRock

03-28-07, 11:41 PM

Just got off the phone with my KNBC contact, to thank him for reverting back from stretch-o-vision.

He said "well, in this case the voice of the people was heard". I believe my/our comments conveyed to him a few days ago right after KTLA had gone from 14:9 back to 4:3 made their executive re-think their decision. They'd been having this discussion about how to present up-converted SD on the HD channel for several years and last week's experiment apparently was voted down after just a week's trial. The fact that they didn't really want to do the work on the graphics at the top and bottom of the screen which were getting cut off with the new presentation I'm sure also contributed to their decision to back out.

I'm guessing they must have had more input than just mine, from other AVS members as well as "civilian" viewers who called or wrote in to complain.

Anyway, only KABC remains.

If you start having frequent interaction between that NBC person you might also want to recommend a few other things. I for one would like to see the HD removed from there logo. It would also be nice for the logo to be moved to the right hand side of the screen for interview shows like Conan and Leno. Ever since they changed the logo to the left hand side it is regularly covering the guests. I liked it much more when the logo was mostly on the desk instead. They move there logo for "Poker After Dark" I don't see why they cant do the same for other shows.

kmillard92

03-29-07, 12:36 AM

If you start having frequent interaction between that NBC person you might also want to recommend a few other things. I for one would like to see the HD removed from there logo. It would also be nice for the logo to be moved to the right hand side of the screen for interview shows like Conan and Leno. Ever since they changed the logo to the left hand side it is regularly covering the guests. I liked it much more when the logo was mostly on the desk instead. They move there logo for "Poker After Dark" I don't see why they cant do the same for other shows.
I agree about moving the logo, but they should keep HD, but it should be smaller in a different font.

andy.s.lee

03-29-07, 03:55 AM

For anyone interested, coverage maps for Los Angeles area transmitters have been posted in this thread (http://www.avsforum.com/avs-vb/showthread.php?p=10127219&&#post10127219).

Best regards,
Andy

benway

03-29-07, 04:47 PM

well NBC stretch o vision is gone
but theres a nice blue line up the left hand side of "Extra" now--
does anyone actually monitor their "TO AIR" signal?

and how about them fixing the 5.1 audio issues?

but progress is being made-- which is good-- and thanks to all those who've helped.

jammer13

04-02-07, 01:58 AM

Jay,

See attached radar plot for the analysis of your location. Longer bars represent stronger signals. Details about each transmitter is listed in the table to the right.

My interpretation:

- The bad news is that you're definitely in the shadows of the hills above Rowland Heights. If you'll notice in the table under "Path", every single channel is either single or double edge diffracted ("1Edge" or "2Edge") as opposed to line-of-sight. The LOS path for most of the channels (see under "LOS_h") passes about 65 meters over your head! But not to worry... too much...

- Height helps, but there's no point in going to extremes (more expense, more trouble, slight improvement). I usually recommend going with a 10 foot pole on the roof using a chimney or tripod mount since that's about as much height as you can get with minimum effort. If you're able and willing to go higher, that's up to you.

- The semi-good news is that there are still a fair number of channels that should be receivable if you get a high gain antenna (e.g., Channel Master 4228, AntennasDirect XG91, or Televes DAT-75). You'll also want to get a low noise-figure pre-amp (e.g. Winegard AP-4700 or Channel Master 7775) in order to minimize signal loss due to cables and splitters. You'll probably be able to receive everything above -100 dBm (under "Rx_dBm") relatively easily and you may actually be able to receive things down to about -110 dBm, give or take. However, as you get close to the lower limits of the system, there will be less margin for variations and errors (e.g., bad weather, multipath, antenna movement, etc.).

- I don't recall off hand whether any of the current digital channels will be moving to VHF in the future, so perhaps someone else could check on this.

- A quad-shielded RG-6 cable is ideal, but standard double-shielded RG-6 should also work just fine if you include one of the pre-amps above. Having extra shielding only helps if you need additional noise immunity due to nearby RF emissions. If the existing cable is something worse, like RG-59, then it should be replaced. RG-59 is more lossy (although that shouldn't matter with the pre-amp) and is more prone to noise ingress.

Although your situation is a bit tougher than average, I still think that a well installed system will get you a good number of the Mt. Wilson digital channels.

I hope this helps. Good luck!

Best regards,
Andy

Well, I said I would update so here it is-

Bought an XG91 antenna plus a Channel Master 7777 (so I can upgrade to VHF later if needed). The antenna is very interesting and comes in pieces you need to put together but no big deal.

I actually tried this setup in my family room with the antenna laying across a box and I was surprised how many channels my TV picked up on scan. KCET, which according to Andy's analysis was going to be fairly challenging to receive (-105.5 Rx_dbm) came in just fine. I used the Antenna RF input on my Sharp Aquos and it's signal strength was about 55-60 whatever that means but I think I've read that's kind of in the low range of acceptability but there were no dropouts.

Anyways, I finally hauled it up and stuck it on my 5 ft mast on the roof and things looked even better. Now KCET is showing about 75 signal strength on the Sharp even after splitting the signal to the E* VIP622. All of the Digital Channels in the area are receiving just fine as far as I can tell - success!

I used R6 QS for most of the run, but not all. There was maybe 15-20ft of standard R6 I used to run down inside the wall to the TV. I'd say total run length is probably on the order of 50'. I also used an F-connector 75-ohm terminator on the unused VHF port on the preamp.

I really like this antenna, it is light and easy to carry and mount and shouldn't provide much of a wind load. It also has a bracket that allows you to tilt the antenna upward which I did at a slight angle (not sure if this helps any but since I'm behind a large hill what the heck). Plus it looks like no other antenna in the neighborhood - it definitely has a unique look.

Thanks to Andy for his useful advice.

Jay

andy.s.lee

04-03-07, 01:49 AM

Dan,

See attached radar plot for analysis results.

My interpretation:

- Looks like a LOT of channels come in very strong. As long as your house is not made of metal, you'll probably do all right with an indoor antenna for most of the channels down to about -70 dBm (under "Rx_dBm"), give or take. It looks like that includes just about everything from Mt. Wilson.

- You might have multipath problems, but that's impossible to predict via simulation. Usually stronger signal levels have a higher probability of having multipath issues. Directional antennas can help if that is the case.

- Due to the large number and relatively high power of the channels, you should probably avoid using any low quality amps or antennas with built-in amps since they may be prone to overload in situations like this. It really depends on how much signal loss you're getting due to building penetration plus the inherent gain of the antenna.

I think the most reasonable thing to try first is a good quality unamplified indoor antenna placed as high as possible. Moving the antenna outside would be even better, but you might find that this is not necessary. The attic is also a good option, if you have access, since the building penetration losses will usually be less and the multipath interference is usually reduced.

I hope this helps!

Best regards,
Andy

DSperber

04-03-07, 02:31 AM

and how about them fixing the 5.1 audio issues?Saturday' night's "Law and Order" on KNBC-DT was missing the dialog, even on the 2-channel PCM stereo mixdown. Only surround sounds.

I called Burbank and they said they were aware of the problem but "nobody was in the department that could fix it".

HA!

I left a message on the voice mail of my "inside Tech contact", though I suspect the problem was out of NY rather than out of Burbank.

hdtvintheie

04-03-07, 03:19 PM

DSperber

04-03-07, 04:16 PM

2) All my SD channels are snowy. If the range of my antenna for VHF is 45 miles and I'm about 36 miles away, how come my DT channels are clearer than my SD channels? I'm assuming the DT channels are on UHF?

3) Is my assumption correct that DT channels are on UHF?Yes, the DT channels are broadcast in the UHF spectrum. But they're not conventional SD UHF transmissions. They are digital transmissions in the UHF frequency spectrum.

They are clearer than the SD channels (in fact, they should be "perfectly clear") because they are digital! They are not subject to any of the normal considerations such as distance which influences analog reception, either VHF or conventional UHF.

With digital channels, as long as the signal strength and quality is above the absolute minimum "lockable" floor that your digital tuner requires, you will have "perfectly clear" picture which will be the identical picture that everybody else in the LA area is seeing no matter where they are located. So as long as your antenna can receive them and your tuner can lock on to them, you've got exactly what the network is broadcasting... no matter how far away you are.

Digital. It's there, or it's not. And if it's there, it's "perfect".

rttrek

04-03-07, 07:59 PM

Digital. It's there, or it's not. And if it's there, it's "perfect".
This is the party line, and I wish it were true. It's not.

Digital artifacts look completely different than analog artifacts, so you won't see any snow, ghosting, or other old analog symptoms of bad reception, but you may see macro-blocking and screen freezes, or experience audio drop-outs, if your tuner loses an adequate signal. This can be caused by momentary signal disruptions caused by, for example, rain, wind or a train parking in front of your antenna :), and partially depends on the quality of your tuner.

SD73

04-03-07, 08:09 PM

hdtvintheie, I'm a little bit closer in in Rancho Cucamonga and I've found the 91XG mentioned above works fantastic for me. No preamps and split to two rooms. I get all available channels and my signal meter is in the 90's for most of them.

DSperber

04-03-07, 09:06 PM

Digital artifacts look completely different than analog artifacts, so you won't see any snow, ghosting, or other old analog symptoms of bad reception, but you may see macro-blocking and screen freezes, or experience audio drop-outs, if your tuner loses an adequate signal.I'm in complete agreement with your comments.

But in general, these digital anomalies will only occur if the signal strength and quality is hovering around the marginal in-or-out lock-or-not level of the tuner. Obviously if there are fluctuations caused by physical factors that cause the signal strength to be sometimes below and sometimes above the crucial threshhold, various types of digital breakup/dropouts will obviously occur.

And even if signal strength is high, if there's something problematic with the encoded datastream (sometimes seen when networks implement hardware or software upgrades) that, too, can cause a complete outage even though signal strength is quite high and well above the floor minimum for tuner locking.

Nevertheless, the question was why his digital picture looked so clear when his analog VHF/UHF reception was pretty iffy. Given a normal steady-state reasonable signal strength, there should be no digital artifacts. And the picture he sees in those circumstances would be exactly "perfect" and would match what anybody else in the LA area would see as long as they, too, were within digital signal range and all the digital tuners could lock.

Rick_R

04-04-07, 12:51 PM

I get DT channels for CBS (2.1), NBC (4.1), CW (5.1), ABC (7.1), KCAL (9.1). Occasional drops for NBC and CW but mostly signal strength is Normal (based on the HTL HD current signal test). CBS and ABC have the strongest signals. I cannot receive KTTV (11.1) at all.

1) How come I cannot get KTTV even though antennaweb says all signals are coming from the same direction? On a clear day I can see the towers (at least I think that's what they are) on Mt. Wilson from my roof, so I don't think the signal is being blocked by a ridge.

Someone said somewhere in this forum that digital KTTV 11 (and KCOP 13) were transmitted from a location behind the first ridge. So even though the approximate location of these transmitters is the same, they are actually not from the same exact spot.

Rick R

twelvepbrs

04-04-07, 06:59 PM

gohd

04-04-07, 07:13 PM

does anyone know the situation with dodgers and angels games in HD over KCAL or KCOP? i thought i read somewhere that all/most dodgers games on KCAL will be in HD (so far this seems correct); are/will any angels games be on KCOP in HD? does KCOP even broadcast anything in HD?
A quick scan of hdsportsguide.com shows a smattering of Dodger games in HD on KCAL (1080i). And, except for the freeway series, very few Angels games in HD locally. What's up with that, Arte!? I see no mention of KCOP (or whatever it's called now).

twelvepbrs

04-04-07, 07:14 PM

A quick scan of hdsportsguide.com shows a smattering of Dodger games in HD on KCAL (1080i). And, except for the freeway series, very few Angels games in HD locally. What's up with that, Arte!? I see no mention of KCOP (or whatever it's called now).
i can't even tell if KCOP (My13LA) broadcasts anything in HD, i checked zap2it, and it listed a few programs in HD, but i'll have to be in front of my TV to verify (i'm at work now :( )

holl_ands

04-04-07, 07:54 PM

Newbie here. I live in Fontana (Zip Code=92336), according to antennaweb, I'm about 36 miles from the transmitters on Mt. Wilson. I installed a ChannelMaster 3016 on my roof with VHF range of 45 miles and UHF range of 30 miles, no preamp, connected to a Hughes HTL-HD receiver. My cable run is around 60 ft.

I get DT channels for CBS (2.1), NBC (4.1), CW (5.1), ABC (7.1), KCAL (9.1). Occasional drops for NBC and CW but mostly signal strength is Normal (based on the HTL HD current signal test). CBS and ABC have the strongest signals. I cannot receive KTTV (11.1) at all.

Got 3 questions:

1) How come I cannot get KTTV even though antennaweb says all signals are coming from the same direction? On a clear day I can see the towers (at least I think that's what they are) on Mt. Wilson from my roof, so I don't think the signal is being blocked by a ridge.

2) All my SD channels are snowy. If the range of my antenna for VHF is 45 miles and I'm about 36 miles away, how come my DT channels are clearer than my SD channels? I'm assuming the DT channels are on UHF?

3) Is my assumption correct that DT channels are on UHF?

Thanks in advance.
1. I took a quick look using RADIO MOBILE (free propagation prediction software).
It shows more and more blockage as you move North above Foothills Blvd.
At the 92336 Post Office location, the signal just skims two peaks at 5 and 19 miles
from the towers, which could affect some frequencies differently than others.
Further South the path becomes more and more unobstructed.

2. Per andy.s.lee's handy TV Station overlay for GoogleEarth, the signal
does NOT pass THRU any of the other TV towers. Although not shown in his overlay,
it probably doesn't pass THRU any other AM, FM or other towers either.
You can also "see" that KTTV-DT, KCOP-DT and KTTV are co-located on same tower,
roughly in the middle of the "farm" and is only 150 yards SE of the KNBC-DT/KNBC's tower.

3. KTTV-DT (FOX, CH65) and KCOP-DT (MNT, CH66) are at the upper end of the UHF band,
which means they suffer from a combination of extra losses compared to other channels.
This could include more propagation loss, more cable loss, more loss in RF Splitters (if used),
reduced tuner sensitivity and (esp. for the R-S antenna) less gain for the higher channels.

4. I also wouldn't rule out the possibility the stations are not operating at full power
and may have "antenna issues".

5. The GoogleEarth overlay also shows Analog KSGA-LP (64 kW) on CH64, located 9 miles
away on the "back" of your antenna. (About 2 miles SE of I215 and Barton Rd).
This can cause "adjacent channel" interference to KTTV-DT on CH65.
If I knew your location to nearest cross streets, I could calculate relative signal levels....

6. A few miles further South (12 miles away, on the "back" of your antenna),
are high power Analog KVMD (CH24) and digital KVMD-DT (CH26).
This "shouldn't" be a problem, but could overload a high gain Preamp.

=========================================
7. So what can you do about it?

a. If you have any RF Splitters, replace with units that will pass at least 1000 GHz.
It also wouldn't hurt to try a SAT RF SPLITTER, which provides extended response beyond 2000 GHz.
Coax "Surge" Protectors can also cause problems--temporarily bypass to test.

b. Try the low gain, high overload Winegard HDP-269 VHF/UHF Preamp.
With the nearest station being only 9 miles away on the "back" of your antenna,
this should provide adequate protection from overload.

c. Try different antenna mounting heights and locations.

d. Try the CM-4228 8-Bay antenna which has higher UHF gain and probably has "enough" VHF gain.
It also has a much higher Front/Back Ratio to help suppress KSGA-LP, Analog KVMD and KVMD-DT.

e. If the CM-4228 doesn't have enough VHF gain for the analog channels,
you could retain the R-S antenna for VHF and combine the CM-4228 to the downlead
with a VHF/UHF Band Separator/Combiner, such as the low-loss Model UVSJ from Pico-Macom:
http://www.picomacom.com/products/display_pico.asp?txtSearch=PMC25

hdtvintheie

04-05-07, 03:35 PM

1. I took a quick look using RADIO MOBILE (free propagation prediction software).
It shows more and more blockage as you move North above Foothills Blvd.
At the 92336 Post Office location, the signal just skims two peaks at 5 and 19 miles
from the towers, which could affect some frequencies differently than others.
Further South the path becomes more and more unobstructed.

2. Per andy.s.lee's handy TV Station overlay for GoogleEarth, the signal
does NOT pass THRU any of the other TV towers. Although not shown in his overlay,
it probably doesn't pass THRU any other AM, FM or other towers either.
You can also "see" that KTTV-DT, KCOP-DT and KTTV are co-located on same tower,
roughly in the middle of the "farm" and is only 150 yards SE of the KNBC-DT/KNBC's tower.

3. KTTV-DT (FOX, CH65) and KCOP-DT (MNT, CH66) are at the upper end of the UHF band,
which means they suffer from a combination of extra losses compared to other channels.
This could include more propagation loss, more cable loss, more loss in RF Splitters (if used),
reduced tuner sensitivity and (esp. for the R-S antenna) less gain for the higher channels.

4. I also wouldn't rule out the possibility the stations are not operating at full power
and may have "antenna issues".

5. The GoogleEarth overlay also shows Analog KSGA-LP (64 kW) on CH64, located 9 miles
away on the "back" of your antenna. (About 2 miles SE of I215 and Barton Rd).
This can cause "adjacent channel" interference to KTTV-DT on CH65.
If I knew your location to nearest cross streets, I could calculate relative signal levels....

6. A few miles further South (12 miles away, on the "back" of your antenna),
are high power Analog KVMD (CH24) and digital KVMD-DT (CH26).
This "shouldn't" be a problem, but could overload a high gain Preamp.

=========================================
7. So what can you do about it?

a. If you have any RF Splitters, replace with units that will pass at least 1000 GHz.
It also wouldn't hurt to try a SAT RF SPLITTER, which provides extended response beyond 2000 GHz.
Coax "Surge" Protectors can also cause problems--temporarily bypass to test.

b. Try the low gain, high overload Winegard HDP-269 VHF/UHF Preamp.
With the nearest station being only 9 miles away on the "back" of your antenna,
this should provide adequate protection from overload.

c. Try different antenna mounting heights and locations.

d. Try the CM-4228 8-Bay antenna which has higher UHF gain and probably has "enough" VHF gain.
It also has a much higher Front/Back Ratio to help suppress KSGA-LP, Analog KVMD and KVMD-DT.

e. If the CM-4228 doesn't have enough VHF gain for the analog channels,
you could retain the R-S antenna for VHF and combine the CM-4228 to the downlead
with a VHF/UHF Band Separator/Combiner, such as the low-loss Model UVSJ from Pico-Macom:

Thanks to holl_ands for the in depth analysis and all the others who replied. All excellent info.

I did discover andy.s.lee's googleearth map. KTTV is actually in front of CBS and ABC (relative to my location) so I'm betting there's probably some sort of interference. My cross street is mango ave and cambria ave by the way.

I'll probably extend the mast or maybe a preamp. As a last resort (don't really want to spend more for another antenna) I'll probably add the CM 4228.

TheRock

04-05-07, 05:36 PM

Can someone explain to me how to install a pre-amp or tell me what is needed to install one. Is it difficult? Do I need to be an electrician?

I cant receive a consistent signal from KCOP using my rooftop antenna. No matter where I point it the best I can do is get a very weak signal that sometimes allows me to watch a program. Even then it usually has tons of breakups. This is the only station I cant receive on a regular basis. I thought a pre-amp might help.

I have the following antenna:

WINEGARD HD7084 PLATINUM SERIES High Definition VHF/UHF Antenna

I don't know much about antennas. In fact my father helped me install mine. Unfortunately he cant help install a preamp so I was hopeful it would be easy enough for me to do myself.

holl_ands

04-05-07, 07:34 PM

Preamps are designed to be installed by the user.

The "best" location is at the top of the antenna mast, however, you can also locate it
at shoulder height if you don't want to drop the antenna.

The Power Module plugs into any convenient AC socket, such as near the TV
(or in the attic) and sends low voltage power up to the mast-mounted Preamp.

See pg 25 in the Channel Master Off-Air Antenna Installation Guide:
http://www.pctinternational.com/channelmaster/prev/_pdfs/guide_AntennaInstallation.pdf
It shows a picture of a twin-lead, 300-ohm input type Preamp that connects directly to the antenna.

To use the more common 75-ohm Preamp input, a balun transformer connects the antenna
to the Preamp's coax input, as shown with this R-S model:
http://rsk.imageg.net/graphics/uc/rsk/Support/ProductManuals/1502507_PM_EN.pdf

BTW: The above R-S 30 dB Gain model is designed for use in the middle of nowhere
and has WAY TOO MUCH gain for urban environments.

Same thing for the Channel Master CM-7777 VHF/UHF 26 dB Gain Preamp.

Recommend you try one of the lower gain Winegard models, such as the
HDP-269 VHF/UHF 12 dB Gain Preamp or one of the 17/19 dB Gain models.

danki6x

04-06-07, 01:29 AM

A quick scan of hdsportsguide.com shows a smattering of Dodger games in HD on KCAL (1080i). And, except for the freeway series, very few Angels games in HD locally. What's up with that, Arte!? I see no mention of KCOP (or whatever it's called now).
All Angel games so far on Fox Sports Net have been in HD. Don;t know about the one on KCOP. I know that does not help with OTA. KCAL has been advertising all Dodger home games in HD this year. Dan

TheRock

04-06-07, 02:30 PM

hobbs47

04-07-07, 01:23 AM

All Angel games so far on Fox Sports Net have been in HD. Don;t know about the one on KCOP. I know that does not help with OTA. KCAL has been advertising all Dodger home games in HD this year. Dan

That would be all Dodger road games I believe.KCAL's production on the Lakers/Dodgers has been amazing.The best baseball/hoops HD PQ I have seen.Who says 720P is better for sports? :D

twelvepbrs

04-07-07, 01:55 PM

That would be all Dodger road games I believe.KCAL's production on the Lakers/Dodgers has been amazing.The best baseball/hoops HD PQ I have seen.Who says 720P is better for sports? :D
it IS better if you have a chitty deinterlacer!

inourgrave

04-07-07, 02:07 PM

I have an AntennaCraft CY-1470 antenna that is on the roof, I am in a two story building but there are other three story buildings surrounding me. I live in Hermosa Beach 90254 on 1st Pl. and PCH. I receive all the big stations for HD on my tv with occasional drops but decent signal strength. I just recently moved to the direct tv hd dvr package and the receiver rates my OTA signal strength at 0%. Is there any recommendations for antennas/amps. Cost is a consideration but I would like this to work. I am 31.8 miles from mt. wilson but rated in the violet section on antennaweb.

eddy_winds

04-07-07, 02:11 PM

OTA in So. Cal is a pain

DSperber

04-08-07, 05:42 PM

StephenMSmith

04-08-07, 07:23 PM

Anybody else notice that the digital audio level for the Masters coverage, especially today Sunday, is the ABSOLUTE LOUDEST EVER RECORDED... even for this network.

As we all know, KCBS-DT is notorious for having the loudest audio level of any local channel. But this is RIDICULOUS!

They must have turned it up again (though I know it may be technically impossible)... to an even higher level.

Are you kidding? I didn't see the masters, but I can't believe CBS HDTV audio could get any louder than it already is... at least 10db higher than NBC and FOX. KABC has gone pretty loud too I notice. If they'd all just to the same level, I wouldn't have a problem.

twelvepbrs

04-09-07, 01:14 AM

OTA in So. Cal is a pain
yeah, it'd be great is someone took some tactical nukes and got rid of all the mountains (except for mt wilson of course)

Johnny5.1

04-09-07, 09:45 PM

joshua927

04-11-07, 02:11 AM

Rick_R

04-11-07, 12:28 PM

All the digital channels in Los Angeles are UHF currently. However, 7, 9, 11, and 13 will move to VHF on 17 February 2009. I believe what you need is a unidirectional antenna to make sure you are not getting reflections off of hills and buildings. Yes you are undoubtedly too close to need an amplifier.

Yes the coax from the satellite system will work fine. In fact the satellite coax needs to be better than OTA needs because of the high frequencies that satellite uses.

Rick R

joshua927

04-11-07, 01:33 PM

RSF_LA

04-12-07, 12:53 AM

Are you kidding? I didn't see the masters, but I can't believe CBS HDTV audio could get any louder than it already is... at least 10db higher than NBC and FOX. KABC has gone pretty loud too I notice. If they'd all just to the same level, I wouldn't have a problem.The issue is the different AC3 (Dolby Digital) dialnorm values between the networks and stations. The value is a negative number The larger the negative number is, the louder the station sounds. CBS and also local KCBS-DT use a dialnorm value of -31db. The opposite extreme is NBC network with a value of -22db, which is 9 db softer. KNBC uses -27db on their the local material and is much louder than the network. Fox uses -25db but KTTV uses -27db. ABC stations don't use network metadata so KABC is a constant -27db. The actual audio itself does not vary much between the stations, but the dolby digital decoder using the dialnorm values creates the differences.

Dialnorm is supposed to reflect the loudness of each program, but no one has implemented it as envisioned.

benway

04-12-07, 11:01 AM

has anyone noticed that the ABC world news is breaking up/dropping out for the past few days?

I think this is a taped re-broadcast of the east coast broadcast

the local ABC news immediatley prior to this is fine, as is the programming afterwards.

So it makes me think that they have issues with tape recording/playback

and again, I marvel at the competence of the broadcast "engineers", who seem not to monitor what they are outputing, in glorious 14:9...

hdtvintheie

04-12-07, 04:51 PM

holl_ands

04-12-07, 06:21 PM

I was reading about preamps and how some have an FM trap to filter out FM signals, so those signals are not amplified and cause interference. Although with my current set up I do not have a preamp, I was wondering if FM signals can still interfere with my HDTV signal? I read somewhere that FM signals only affect higher VHF channels like 7-13? Is that accurate?

Also, I know preamps can boost the signal over long cable runs. Would a 60 ft cable have significant signal loss that I would need a preamp?

Thanks!
FM frequencies are in the 20 MHz wide band just above CH6.
Most VHF/UHF Preamps use separate VHF and UHF amplifiers, so FM overload does not affect UHF.

However, most VHF Preamps (even in a combo VHF/UHF Preamp) use the same wideband
amplifier for the entire VHF band (CH2-13, including FM). Hence FM overload could affect
ALL VHF channels, depending on the nature of the intermod products.

A Preamp overcomes the loss in the downlead (4-6 dB), plus the Noise Figure "Loss" in your tuner
(est. 7-13 dB), improving the ultimate sensitivity by about 10 dB...but only if the Preamp's
non-linear intermod products are no higher than the thermal noise floor...which is why it is
difficult to predict whether a Preamp improves or degrades performance.

Best best is to start with the very low gain, very high overload W-G HDP-269 and see what you get....
At your distance it should help quite a bit....

BTW: You can check to see how far away FM stations are at www.fccinfo.com
The only significant station is KFRG on the backside of your antenna, about 15 miles away, so go
ahead and switch in the FM Trap. It would only affect CH6 anyway, so shouldn't affect anything you watch.

RudyG

04-12-07, 07:02 PM

hi joshua. while you are waiting for the gurus to answer your question I thought I'd chime in with the answers I have seen to the exact questions you are asking, in this thread.
I of course highly recommend that you read this thread as it is filled with useful information. If you don't have the stomach to read the entire thread at least search out and read the posts by andy.s.lee and holl_ands.
Also andy posted a link to a tool that he developed that works with google earth application to help us locate the Mt. Wilson antennas and point ours at them.

Hello all.

I live in La Crescenta, CA. I have a clear view to Mount Wilson which is about 11 miles away (straight, point to point distance).

I'm currently using a small indoor RCA branded antenna that I had for years. It is now hooked up to my Philips 50" plasma with built in HD tuner. I didn't have any big expectations but to my pleasant surprise I consistently get 2.1, 4.1, 5.1, but my 9.1 and 11.1 are very choppy and unreliable. I figured that all other channels run on UHF and the 9.1 and 11.1 run on VHF and therefore, my existing antenna does not handle the VHF signals well. Now I need 9.1 and 11.1 for the Lakers, Dodgers and the American Idol. Having said that... It seems as if an outdoor antenna will be a really good solution for me.

Now this is where the predicament begins...

1. What Antenna to choose (I know it is different for everyone but for my situation, what would be the safest choice?) All my stations come from one direction (Mt. Wilson), so do I get a unidirectional or bi, multi-directional?

For a strong signal, I understand that a highly directional antenna is recommended. As opposed to multi directional. I've heard the Channel Master 4228 mentioned quite a bit by those same gurus. So that may be a start for you, as far as something to look at and research.

2. What are pre-amps and amps? By the name, it seems as if they "amplify" existing signals, considering my relative close distance, should I consider getting them? (What do they do, what are their differences and do i need them?)

My understanding is that the signal amplifiers amplify the signal from your rooftop antenna to your television set. Not the signal from the television tower to your rooftop or indoor antenna. They are used in situations when the signal has to travel over very long cables or to many many television sets.

I plan to buy the antenna and install them to the roof and run the cable down to my TV. Would any kind of coax cable suffice? I have one direcTV dish that was installed by the previous owner of the house. Can I use that DirecTV dish coax cable instead of buying new ones?

Good Luck.
HTH.
Rudy

holl_ands

04-12-07, 07:42 PM

Hello all.

I live in La Crescenta, CA. I have a clear view to Mount Wilson which is about 11 miles away (straight, point to point distance).

I'm currently using a small indoor RCA branded antenna that I had for years. It is now hooked up to my Philips 50" plasma with built in HD tuner. I didn't have any big expectations but to my pleasant surprise I consistently get 2.1, 4.1, 5.1, but my 9.1 and 11.1 are very choppy and unreliable. I figured that all other channels run on UHF and the 9.1 and 11.1 run on VHF and therefore, my existing antenna does not handle the VHF signals well. Now I need 9.1 and 11.1 for the Lakers, Dodgers and the American Idol. Having said that... It seems as if an outdoor antenna will be a really good solution for me.

Now this is where the predicament begins...

1. What Antenna to choose (I know it is different for everyone but for my situation, what would be the safest choice?) All my stations come from one direction (Mt. Wilson), so do I get a unidirectional or bi, multi-directional?

2. What are pre-amps and amps? By the name, it seems as if they "amplify" existing signals, considering my relative close distance, should I consider getting them? (What do they do, what are their differences and do i need them?)

I plan to buy the antenna and install them to the roof and run the cable down to my TV. Would any kind of coax cable suffice? I have one direcTV dish that was installed by the previous owner of the house. Can I use that DirecTV dish coax cable instead of buying new ones?
Since you are only 10 miles away, you shouldn't need much of an antenna. CM4228 would be overkill.

And, or course, you shouldn't be using ANY sort of amplified antenna, Preamp or distribution amps,
cuz they are likely to overload both the Preamp input and the HDTV input.

Since indoors doesn't work very well, either you aren't receiving the signal via a window facing
Mt Wilson and/or you have very serious multipath....maybe a strong bounce from hills South-West of you.

Hence, it's terrific to see that you are committed to an outdoor antenna....after that,
it's how big do you want to go....
Good, economical, choices would be any of the 4-Bay Antennas: C-M CM-4221 (aka CM-3021), W-G PR-4400 or A-D DB-4.
Antennas Direct (A-D) also makes the smaller 2-Bay DB-2.

If you want, you could use any of the above with a short pole attached to a building ledger (on the Mt Wilson side),
mounted slightly BELOW the eves, in order to "block" the MP bounce from the S-W.

Any of the R-S, C-M or W-G VHF/UHF Combo antennas would also be good, if you have the space for guy wires.
At 10 miles, VHF is going to get in no matter what you use, but the VHF/UHF combo's will suppress
VHF multipath coming in from the SW.... which will become more important by Feb 2009.
In this respect, VHF/UHF combo would be better than CM-4228's so-so VHF performance.

PS: I still would recommend CM-4228 for hi-vhf reception in most non-fringe reception areas,
but your topography can readily be seen to be highly prone to multipath reflections....
So the "best" antenna (after Feb 2009) in your area would probably be a VHF/UHF Combo.

======================================
If you want to share the DirecTV downlead coax, a pair of TV/SAT DIPLEXERs will do the job.
However, D*'s new MPEG4 capable systems can not share the downlink with TV signals, so you may
want to go ahead and install another RG-6 coax (double or quad shield).

BikeGuy

04-13-07, 12:28 PM

Hi All!! Newbie here from San Fernando Valley.

Ok... so I'm diving into DTV (finally!) and trying to get started on my OTA setup. Did all the precursor work to get my bearings (AntennaWeb, etc...) and here is what I found.

The major transmitting site for the San Fernando Valley is obviously...Mt. Wilson. It is about 21 miles NE from my location in Studio City. It looks like I have a pretty clear shot from my rooftop with the exception of a ridge that appears to scoot across Glendale. But here is the bad news => Burbank Airport. The airport seems to lie dead center in the middle of my path, about 10 miles out. As (bad) luck would have it, my compass reading to hit Mt. Wilson puts my Antenna looking straight down the take off runway. You don't even need a compass to figure this out. You can see the jets coming straight for Studio City where they do a quick bank (right over my house) and head north.

If I'm understand correctly from other posts, this will introduce a lot of interference, reflection, multipath, etc... as the signals get bounced around by the jet traffic.

Anyone in SFV (Studio City, Sherman Oaks, Burbank) have any luck with OTA in this situation. I also see a lot of posts from OC so maybe someone with experience around John Wayne could chime in.

What would be a good antenna choice to pull this off???

Thanks to all in advance.

Xylon

04-13-07, 05:48 PM

Only one way to find out. Install your anteanna and see for yourself.

holl_ands

04-13-07, 09:12 PM

If you have problems, you could use a two antenna system with equal length cables to an RF Combiner/Splitter.
Try to get as much separation as possible, such as on opposite sides of your house....
Should reduce the time that one antenna is being "blocked", but there is still the chance of both being blocked for a shorter period of time....

Rick_R

04-16-07, 12:13 PM

BikeGuy,

My Son is in Valley Village and I installed his HDTV and used a FM dipole antenna taped to the wall and got every digital channel. You should have no problem especially if you get a rooftop antenna.

Rick R

BikeGuy

04-16-07, 01:49 PM

Rick_R,

Thanks for the info on Valley Village. That loc would certainly have the same issues. I was conjuring up a complicated dual-antenna scenario like hol_ands suggested. I'm very surprised an FM atenna "tapped to the wall" did the trick. My only concern is that I always get a "ghost" on KCET matter how I point my antenna, which is on the roof. But at least with digital it's all or nothing proposition.

Thanks all for the reponses. As the first poster suggested, I'll just start playing with it.

Regards...

joshua927

04-17-07, 02:26 AM

I went ahead and ebayed me an outdoor antenna for about $25 + 10 shipping.
I get about 35 digital channels and am very pleased.

Is there a channel lineup/ schedule that I can view online?

Thank you!

holl_ands

04-17-07, 02:45 AM

www.titantv.com
And it can be tailored to display ALL, selected or ONLY HD.

RudyG

04-17-07, 04:41 PM

www.titantv.com
And it can be tailored to display ALL, selected or ONLY HD.

I also use http://www.zap2it.com
As TitanTV doesn't appear to have the correct cable listing for my area of West LA.

Rudy

narkspud

04-20-07, 10:05 AM

The KCBS morning news crew just dropped a not-so-subtle hint that their newscast is going HD Monday morning.

Vera Jimenez in High Definition. Technology is a wonderful thing.

twelvepbrs

04-20-07, 01:28 PM

The KCBS morning news crew just dropped a not-so-subtle hint that their newscast is going HD Monday morning.

Vera Jimenez in High Definition. Technology is a wonderful thing.
not sure who that is, but i'd much rather see KCOP's late news with laura sanchez (i think that's her name) in HD...she has tig ole bitties

narkspud

04-21-07, 08:39 AM

not sure who that is, but i'd much rather see KCOP's late news with laura sanchez (i think that's her name) in HD...she has tig ole bitties

Vera is KCBS's morning traffic reporter. You really should tune in . . . sounds like you'd like her.

celticpride

04-21-07, 11:12 AM

CBS starts HD NEWS satuday at 5p.m. local time,on friday nights 11 p.m. news they showed part of the new HD studio and said BOTH CBS AND KCAL would have there news in HD starting saturday april 21. btw its listed in directvs guide at 5p.m. as HD.

wxman1969

04-21-07, 11:18 AM

When it rains, or in this case today, just after it rains, my UHF signal decreases with channels starting at around 43 (which is KCAL- 9) and going all the way to 69. In fact, I basically get 0 signal starting with 53 (KABC-7). The signal for channels under 43 are pretty much full strength. Is this indicative of a problem on my end? I know it snowed on Mt. Wilson yesterday, but I would think if there was a problem there or if I had a hardware problem that I wouldn't get any signal on any of the channels. I am about 70 miles from Mt. Wilson, but most of the time I have no problem getting a strong signal from all the UHF stations.

holl_ands

04-21-07, 04:10 PM

Larry Parker

04-21-07, 10:58 PM

FINALLY! Jackie Johnson's and Mia Lee's tits in high definition! That'll practically be 3D. Or is it 36D :)

wxman1969

04-22-07, 01:04 AM

Weather (even when it isn't raining) can affect how signals are refracted in the atmosphere.

However, it is also possible that moisture is getting into your antenna/preamp/downlead.

Most 300-ohm twin-lead wiring is particularly susceptible, since it experiences much higher
loss along the transmission line when it's wet.

But wouldn't that affect all channels rather than just the higher numbers? Almost everything from channel 43 and below had a signal of at least 80. And the ones above about 53 were totally dead. I wondered if moisture may have been an issue, but I don't understand why it's only impacting certain channels.

holl_ands

04-22-07, 04:36 AM

But wouldn't that affect all channels rather than just the higher numbers? Almost everything from channel 43 and below had a signal of at least 80. And the ones above about 53 were totally dead. I wondered if moisture may have been an issue, but I don't understand why it's only impacting certain channels.
Moisture will usually affect higher channels more than lower ones.
The higher channels are also the ones most affected by propagation loss,
cable/RF Splitter/etc loss and sometimes reduced antenna gain....

However, since it also affects the VSWR, different channels can be affected
in different ways, depending on the length of the cables wrt channel wavelength.
Hence affected channels can be seemingly unpredictable....

speck2001

04-22-07, 04:06 PM

Hi All!! Newbie here from San Fernando Valley.

If I'm understand correctly from other posts, this will introduce a lot of interference, reflection, multipath, etc... as the signals get bounced around by the jet traffic.

Anyone in SFV (Studio City, Sherman Oaks, Burbank) have any luck with OTA in this situation. I also see a lot of posts from OC so maybe someone with experience around John Wayne could chime in.

What would be a good antenna choice to pull this off???

Thanks to all in advance.

I'm in Burbank and just bought an HDTV with antenna yesterday. I bought the $19.99 Philips UHF/VHF/HDTV indoor antenna. I am able to see all the HD networks EXCEPT for CBS HD. No matter how I tweak it, even with good signal strength, the channel doesn't show up when I scan. I have no idea why.

BikeGuy

04-22-07, 04:32 PM

FINALLY! Jackie Johnson's and Mia Lee's tits in high definition! That'll practically be 3D. Or is it 36D :)

GUYS....COME ON... Ok...this is most likely an "all guys" board... but let's have a little respect in case a few ladies post here.

BikeGuy

04-22-07, 04:50 PM

Speck2001,

Interesting info. I looked at AntennaWeb and CBS-HD transmitts fairly high on the UHF spectrum on freq 60. Maybe your indoor antenna is dropping out on high UHF. But FOX-HD show as freq 65. So if you get FOX-HD not sure why CBS-HD would not come. Maybe the CBS signal is skimming across the top of your house. Spend $20 at RS and run the little puppy up to the roof on a 30 ft. coax. See what happens as a test.

My HDTV is still on backorder from my online electronics dealer. So I can't see a darn thing yet!!

Thanks for the update. It looks like the air traffic issue is not that big a deal...other than "maybe" CBS-HD. Good to know!

csrini1

04-22-07, 04:55 PM

I'm in Burbank and just bought an HDTV with antenna yesterday. I bought the $19.99 Philips UHF/VHF/HDTV indoor antenna. I am able to see all the HD networks EXCEPT for CBS HD. No matter how I tweak it, even with good signal strength, the channel doesn't show up when I scan. I have no idea why.

That was the reason why i upgraded my 20 dollars antenna to phdtv3 phillips antenna from amazon for 23 dollars, this is an amplified antenna, and now i can see cbs too. Having said that i think now that the terk amplified antenna,terk hdtva, from amazon for 35 dollars should be even better. but did not try the terk antenna.

with a 100ft rg6 cable, i put the antenna outside and when i rescanned the channels, i got 10 more channels with philips phdtv3. you might be better off to try this.

StephenMSmith

04-24-07, 10:57 PM

RudyG

04-25-07, 12:38 AM

nathan118

04-25-07, 06:38 PM

Anyone notice a bitrate drop on CBS, specifically during their primetime shows? It goes back up by the time Letterman comes on. Did they start multicasting?

arbie

04-25-07, 08:57 PM

Channel 60's datarate looks unchanged during their local news at 17:55. I'll check later tonight during prime time.

PID Usage Chart
0x0000 (0.09% ~ 0.02 Mbps) 0x0000 MPEG-2 Program Assocation Table
0x0030 (0.02% ~ 0.00 Mbps) 0x0030 MPEG-2 PMT for program 1
0x0031 (77.67% - 14.37 Mbps) 0x0031 MPEG-2 Video for program 1
0x0034 (2.03% ~ 0.38 Mbps) 0x0034 AC-3 Audio for program 1
0x0035 (1.02% ~ 0.19 Mbps) 0x0035 AC-3 Audio for program 1
0x1d00 (0.03% ~ 0.01 Mbps) 0x1d00 ATSC EIT-0
0x1d01 (0.02% ~ 0.00 Mbps) 0x1d01 ATSC EIT-1
0x1d02 (0.01% ~ 0.00 Mbps) 0x1d02 ATSC EIT-2
0x1d03 (0.00% ~ 0.00 Mbps) 0x1d03 ATSC EIT-3
0x1e00 (0.08% ~ 0.01 Mbps) 0x1e00 ATSC Event ETT-0
0x1e01 (0.03% ~ 0.00 Mbps) 0x1e01 ATSC Event ETT-1
0x1e02 (0.01% ~ 0.00 Mbps) 0x1e02 ATSC Event ETT-2
0x1e03 (0.01% ~ 0.00 Mbps) 0x1e03 ATSC Event ETT-3
0x1ffb (0.08% ~ 0.02 Mbps) 0x1ffb ATSC Base PID (TVCT, MGT, RT, STT)
0x1fff (18.90% ~ 3.50 Mbps) 0x1fff MPEG-2 NULL Packet

arbie

04-25-07, 11:10 PM

Here's the datarate at 20:05 during Jericho:

Tuner: Channel 60 (749 MHz)
Signal: Locked SNR: 28.4 dB
Network Type: ATSC

PID Usage Chart
0x0000 (0.09% ~ 0.02 Mbps) 0x0000 MPEG-2 Program Assocation Table
0x0030 (0.02% ~ 0.00 Mbps) 0x0030 MPEG-2 PMT for program 1
0x0031 (79.92% - 14.78 Mbps) 0x0031 MPEG-2 Video for program 1
0x0034 (2.03% ~ 0.38 Mbps) 0x0034 AC-3 Audio for program 1
0x0035 (1.02% ~ 0.19 Mbps) 0x0035 AC-3 Audio for program 1
0x1d00 (0.03% ~ 0.01 Mbps) 0x1d00 ATSC EIT-0
0x1d01 (0.02% ~ 0.00 Mbps) 0x1d01 ATSC EIT-1
0x1d02 (0.01% ~ 0.00 Mbps) 0x1d02 ATSC EIT-2
0x1d03 (0.00% ~ 0.00 Mbps) 0x1d03 ATSC EIT-3
0x1e00 (0.08% ~ 0.01 Mbps) 0x1e00 ATSC Event ETT-0
0x1e01 (0.03% ~ 0.00 Mbps) 0x1e01 ATSC Event ETT-1
0x1e02 (0.01% ~ 0.00 Mbps) 0x1e02 ATSC Event ETT-2
0x1e03 (0.01% ~ 0.00 Mbps) 0x1e03 ATSC Event ETT-3
0x1ffb (0.08% ~ 0.02 Mbps) 0x1ffb ATSC Base PID (TVCT, MGT, RT, STT)
0x1fff (16.65% ~ 3.08 Mbps) 0x1fff MPEG-2 NULL Packet

arbie

04-26-07, 12:49 AM

BTW, here are the video datarates I'm seeing at 21:34, 25 April 2007, for LA's 9 HD broadcasts:

Ch 2.1 (60) - 14.78 Mbps
Ch 4.1 (36) - 14.47 Mbps
Ch 5.1 (31) - 13.53 Mbps
Ch 7.1 (53) - 11.87 Mbps
Ch 9.1 (43) - 16.88 Mbps
Ch 11.1 (65) - 15.11 Mbps
Ch 13.1 (66) - 14.58 Mbps
Ch 28.1 (59) - 9.35 Mbps
Ch 50.1 (48) - 12.19 Mbps

speck2001

04-26-07, 01:15 AM

Well, I extended the rabbit ears on my Philips indoor antenna and that finally brought in DT CBS-2.1, but I lost DT-13 (no loss to me; there's nothing worth watching since Enterprise was cancelled).

dano1122

04-26-07, 02:05 AM

does anyone here get pissed off at the huge difference in volume on OTA digital broadcast between a program and the commercial breaks. it literally seems like TWICE as loud during breaks. this is just plain ridiculous, i'm going to get repetitive stress injury from handling my remote... i notice it on every channel, some are worse in the difference depending on the program. e.g. a program that is mostly easy dialogue (like a sports report on cough kcal9 cough) and then to a loud car commercial. IT IS LITERALLY DOUBLE THE PERCEIVED VOLUME IF NOT MORE WHEN THE BREAK HITS AND THIS CARRIES THROUGHOUT ALL COMMERCIALS USUALLY. how can this be professional broadcast tv? this has got to stop. you're telling me i'm gonna come home from work dead beat and then get ear banged by networks and their advertisers just trying to enjoy some normal tv watching?

it seems like the dialogue normalization value is maxed out on some commercials. what is the point of this, to shout at people?

narkspud

04-26-07, 10:42 AM

IT IS LITERALLY DOUBLE THE PERCEIVED VOLUME IF NOT MORE WHEN THE BREAK HITS AND THIS CARRIES THROUGHOUT ALL COMMERCIALS USUALLY. how can this be professional broadcast tv?

it seems like the dialogue normalization value is maxed out on some commercials. what is the point of this, to shout at people?

This is not a new thing at all . . . it's been going on since the 60s. Broadcasters want you to watch the commercials, so they make them louder to get your attention. The tools they're using to do this have improved, but the strategy (and the complaints) have been around for over 40 years.

In the past, the effect was muted (slightly) by the audio processing on the transmission end and the limited bandwidth of the NTSC audio signal. Now you're getting the full digital dynamic range, or lack thereof.

That having been said, I have noticed that KCBS and KCAL do seem to be having audio level issues since they moved to their new "state-of-the-art" facility. Hopefully it's just some bugs that need to be worked out of the installation, or an audio engineer that needs a good speaking to.

While we're on the topic of audio, am I the only one who thinks KNBC are fools for running all their news audio through a crappy-sounding noise gate?

Yep, thought so.

nathan118

04-26-07, 08:28 PM

bmwf1techie

04-27-07, 03:47 PM

Hoping someone can help me solve an interesting problem. For the past 3 months I was unable to tune in 2-1 and 9-1 and I used to be able to. I would do channel scan after scan and it would not lock. Well the other day, I scanned again and it locked them both in perfectly on the 1st scan. I am 21 miles from the transmitters and am using a Silver Sensor in my attic. Would there be any type of temporary interference that can cause me difficulty in tuning in channels? Any insight would be great. Thanks.

andy.s.lee

04-28-07, 01:28 AM

I have just move to a condo across the street in MDR. My indoor antenna picked up all the local OTA HD w/o only a few glitches on occasion. I am pretty sure that this was due more to multipath/reflection than anything else.

In my new condo, this indoor antenna picks up KCAL and 50-1 (KCET?) but nothing else. Does that provide some clue as to what I need to do to get WB and the other PBS station (28-1)? Are KCAL and 50-1 HD towers in different location that everyone else?
It looks like all the channels are coming from pretty much the same direction (within a degree of each other, see attached plot). You should have a clear shot toward all the channels unless you happen to be in the shadow of the hills in Culver City. Are you a side of the building that is facing toward the transmitters?

If you're in the clear, then I'd say your problem may be a lot of multipath. Perhaps your new location is right in the path of some major reflected signals. First thing to try is moving the antenna to different rooms to see if there's any significant improvement. Try moving the antenna outside, if possible, to see what happens.

If no spots look any better, then you might be dealing with a signal level problem. If the building has aluminum siding or foil-backed insulation in the walls, then you might be having a problem with simple signal blockage. But I'd check out the multipath situation first, since that's the more likely culprit.

I hope this helps!

Best regards,
Andy

dublus

04-30-07, 05:53 PM

Hello all,

I've been a long time lurker and have very much appreciated the helpful advice that is so abundant here. After enjoying OTA for about a year now my setup has recently taken a turn for the worse.

A little background:

We live in Moorpark (93021) which is about 45 miles west of Mt. Wilson. Our two-story house is on a hill just above the local junior college (Moorpark College, duh). We have a chimney-mounted Channel Master 4228 sitting about 12 feet above the roofline. There's about 60 feet of coax feeding a Dish Network VIP622.

As I said above, we have had very good reception for the last year. When I first put the antenna up, there were some frequent breakups on channels 5 and 13. I had another 2 feet of antenna mast to work with and by raising the antenna up just that extra 2 feet the breakups almost completely disappeared.

A few months ago we switched from a Dish 942 to our current 622. Nothing changed reception-wise.

Then, about three weeks ago we started having very frequent breakups on just about every channel (2, 4, 5, 7, 9, etc.). At first I thought the weather might have gotten to something so I re-worked all of the connections - no change. Then I thought maybe something was causing a reflected signal to hit the antenna so I tried all sorts of new directions for the antenna to point to. This experiment yielded an interesting piece of information. I swung the antenna far enough around that it was pointing to San Diego. I started getting channel 10 (from San Diego) clear as can be. I left the antenna that way through several hours and never saw one breakup. This bit of information gave me a pretty good feeling that there was nothing wrong with my setup. Nice to know I can get that channel if I ever want to but it doesn't fix the problem.

Still trying to eliminate any possibility, I thought it could be the receiver or the coax. To address both of those possibilities I temporarily strung a new cable from the roof through a window into the master bedroom where the 942 had been moved. No change. Just to be sure I ran the same cable through a downstairs window to the 622. No change. Remembering what a difference a measly two feet of antenna height had made, last Saturday I bought a new 20 foot mast to replace the ten foot one. The signal strength numbers went up a little but... no change.

I should explain the nature of what happens when the signal drops out. Take channel 9 (KCAL) for example. Most of the time the signal strength for this channel is between 95-100 on the 622. If I continually monitor the signal, it will change from 100 to 0 within one second, sit at 0 for anywhere between 1/2 and several seconds, then jump back to 100. Pretty much all the channels do this. The only difference being how often it occurs. With the better ones, it's once every minute or two, the others it's more often.

I have now run out of things to try. Based on what I've read here it seems like multipath. From what I remember reading, it seems like the 4228 is a good one for being highly directional.

Is there anything left for me to try?

Sorry for such a long post but I am at the end of my rope.

Rick_R

05-01-07, 12:55 PM

dublus,

Hi neighbor. I am in Simi Valley... actually the east end of Simi Valley. As that is I am closer to the Santa Susanna peak and have difficult reception. I do get every digital station reliably except 13. I aim my antenna a little to the north of Mt Wilson (maybe 8 to 10 degrees north). This has little effect on the direct signal but there is a second signal arriving at my antenna from a pass in the hills about 25 degrees south of the direct signal and this reduces that signal thus giving me better reception.

Your problem is undoubtedly multipath also. You are getting a reflected signal somewhere. You can try to avoid this by reaiming your antenna. Aim it a little to the south or north of Mt Wilson. This way you will hopefully reduce the multipath.

Hope this helps.

Rick R

dublus

05-01-07, 02:26 PM

Hi Rick_R,

Thanks for the reply. I have tried many different antenna directions but maybe I wasn't quite as carefull in the direction you recommended. I will try that, hopefully tonight after work. I'll just keep moving it north a degree or so at a time and see what happens. There must be something new between our house and Mt. Wilson that is reflecting the signal. Now that I have a higher antenna I can afford to be "off center" from the direction of the signal a bit.

Would the tilt of the antenna make much difference? Because of the way the chimney is ornamentally constructed, the mounts cause the antenna to tilt back and to the side a bit with respect to the signal. I can pull it down straighter with wires if I need to. Should this make a difference? If so, why did it wait a year to matter? Thanks again.

mkpl

05-02-07, 02:20 AM

... Would the tilt of the antenna make much difference? Because of the way the chimney is ornamentally constructed, the mounts cause the antenna to tilt back and to the side a bit with respect to the signal. I can pull it down straighter with wires if I need to. Should this make a difference? ...

I see an effect in my setup. I put a CM 4228 in my attic. I can only get KTTV-DT if I tilt it slightly downward. Any ideas why?

JRBurn

05-02-07, 10:10 AM

Hello, I’ve been trying to get KCET HD 28 here in L.A. and have been unsuccessful, I have a clear line of sight to Mt. Wilson (I can see the towers from my roof) according to Antenna Web I’m 17 miles from Wilson. My antenna is a 91XG uni-directional UHF antenna from Antennas Direct, no amp. All my station in L.A. has a compass orientation between 87 – 90.
I set it up in my DirecTV HR20-700 and here’s a list of the L.A. channels in my guide and strength (some of these station I’ve never knew about)
2-1 KCBS 90%
4-1 KNBC 70% All
5-1 KTLA 90% All
7-1 KABC 26% All
9-1 KCAL 90%
11-1 KTTV 0%
13-1 KCOP 0%
18-1 KSCI 98% All
22-1 KWHY 90%
23-1 KVMD 0%
24-1 KVCR 0%
28-1 KCET 0% All
30-1 KPXN 100% All
34-1 KMEX 70% All
40-1 KTBN 0% All
44-1 KXLA 70% All
46-1 KFTR 65%
50-1 KOCE 55% All
52-1 KOEA 75% A (Ventura station?)
54-1 KAZA 65%
56-1 KDOC 85%
57-1 KJLA 65% All
58-1 KLCS 0%
62-1 KRCA 100%
64-1 KHIZ 0%

The only OTA station I would like to receive is KCETDT and I cannot, occasionally it will spike 100% on my signal strength, thanks for the help.

csrini1

05-02-07, 05:22 PM

I don't know much, but i use philips hdtv antenna phdtv3 from amazon for 22 dollars and i get all of the channels you mentioned, i live in zipcode-91007.

Rick_R

05-03-07, 12:19 PM

Hello, I’ve been trying to get KCET HD 28 here in L.A. and have been unsuccessful, I have a clear line of sight to Mt. Wilson (I can see the towers from my roof) according to Antenna Web I’m 17 miles from Wilson. My antenna is a 91XG uni-directional UHF antenna from Antennas Direct, no amp.

The only OTA station I would like to receive is KCETDT and I cannot, occasionally it will spike 100% on my signal strength, thanks for the help.
If you are 17 miles and can see the transmitter towers it is possibel the 91XG is too powerful and you are overloading your receiver. If the signal is going from 0 to 100 that means that you have multipath problems or are overloading your receiver. Probably you are overloading your reciever. At 17 miles and line of sight you probably could get all stations with a coat hanger indoors.

Earlier in this thread I mentioned that I set up my Son's HDTV in Studio City at about 20 miles and used a FM antenna taped to the wall. Got all digital channels.

Rick R

dublus

05-03-07, 02:10 PM

Well, I thought I would give an update on my recent reception woes.

Over the last couple days I have gradually lowered the antenna, checking signal at each stop while swinging it from north to south in increments of a few degrees, starting from where I can get a little signal and ending where the signal dies out.

After all that, it seems obvious that no matter where the antenna is with respect to height or aim angle, it is awash in multipath. I just can't imagine what could be "out there" that wasn't previously there for over a year that has caused this problem to suddenly occur.

Am I completely out of options? Is there such thing as an antenna that has a sufficiently narrow "look angle" that, if aimed directly at the tower(s), it would help eliminate the unwanted reflections? Is there a standalone receiver that is superior at handling multipath? Would attenuating the signal just the right amount help? I was wondering about raising the antenna up as high as I can get it to collect the maximum "good" signal, but install an attenuator so only the strongest, direct signals could get through. I suppose that might work for only one channel at a time depending on the attenuator. Or maybe it would be easier to fly to Baghdad, buy an old lamp, polish it up and see...

bmwf1techie

05-03-07, 02:26 PM

Did anyone watch the Laker game last night on KCAL-DT? I am curious to know how PQ was. I watched the game on TNT-HD via D* and the game looked horrible. Lots of pixelation and an overall soft picture. Am curious if it looked better on KCAL.

alaskaman1666

05-03-07, 07:11 PM