Any advice/tips for climbing an antenna tower? I'm sure someone here has experience climbing their own. It's about 35 feet tall and 25 of those are attached to the house. I trust its integrity and I'm sure I would be fine climbing it unsupported but I would feel much better if I had some sort of harness to wear, protecting myself from any unforeseen slip of the foot. Any suggestions?

Hire a professional. Repairs to humans are too expensive.

Even though I was "Tower Qualified," I usually climb my 50' "Ladder Tower" all the time without a harness and no spotter. I have complete confidence in my abilities and the tower.

That said, when I do major work on the tower, I wear my fatigue pants, for carrying a couple of wrenches and screwdrivers (I've only dropped a 7/16" combo wrench once) and use a good 80' cotton rope to tie myself (I wrap the rope around me and the tower about six times) to the tower and to have enough length to raise large components.

I like that idea about a macrame belt, although I would weave in a couple of "D-rings" to clip to.

I've never used a safety belt, but it is crazy not to. I've been "bonked" while working high up twice. One time was when I was installing a temperature sensor on the back side of an Andrew 4.5 meter dish on top of the ABC News Building headquarters, a gadget that I had clamped onto a horizontal rod swung down and hit me solidly on the side of my head. If I had been facing the direction it swung from and if it had instead hit me in the face, I just might have reacted to it in a way that could have led to my falling.

...(I've only dropped a 7/16" combo wrench once)...

I once had a hammer fall out of my tool belt (on a sloped roof, not on a tower) and miss the hood of a Rolls Royce by less than a foot. The way I see it is, if your ever going to do something stupid that gets your insurance canceled, it might as well be damaging a Rolls Royce.

Talking about stupid and cars, when I was doing Primestar installs, I had a customer who decided to quickly remove a tree so that I wouldn't leave without installing the system. Needless to say he was in such a rush to get the system that he felled the tree right across the hood of his car. :)

Since the tree was now down and the damage was done, he had me continue with the install, so that the day wasn't a total loss.

I should instead buy another antenna specifically for channel 19 at 45 miles and keep the 4228 pointed where it is.

Unless you separate the cabling by a switch, or install a jointenna type device, this could easily cause more problems than it solves. It may take quite a bit of trial and error, otherwise, since the signals from the two antennas will interfere with each other.

Unless you separate the cabling by a switch, or install a jointenna type device, this could easily cause more problems than it solves. It may take quite a bit of trial and error, otherwise, since the signals from the two antennas will interfere with each other.

I have a jointenna for channel 19.

So does anyone have an opinion and or experience on a 91XG vs. HD-9032. Maybe a better candidate? I'm trying to get channel 19 which is about 50 miles.

Callsign Chan Network Dist(mi) Path NM(dB)
WBKI-DT 19 (34.1) CW 49.5 2Edge 14.8

Ok, I think everyone here knows I have a horizontal stack of 91XG's at 55' in the air. (They work great)

Here is the crazy projects I am thinking about.

1) Stack 4 - 91 XG's Vertically on the legs of the tower to try and get some Detroit coverage during the day. (On the last two section of tower). :eek:
- I have 5 of them, but I think I am just wasting to much signal with couplers. My horizontal stack is not reliable with this market.

2) Do a quad box style of 91 XG's at 20'.
- These will ONLY be 20' off the ground. I can shoot them 5- 10 degrees of the horizon.

Maybe, I am just wasting my time.

And yes, I do have a garage full on antennas!

Any ideas, or just forget about it all and have a brewski.

Sounds like you're already in the brewskies. :)

Hey, it's a hobby. If you want to try it out, go right ahead. Just be careful.

1) Stack 4 - 91 XG's Vertically on the legs of the tower to try and get some Detroit coverage during the day. (On the last two section of tower). :eek:
- I have 5 of them, but I think I am just wasting to much signal with couplers. My horizontal stack is not reliable with this market.

2) Do a quad box style of 91 XG's at 20'.
- These will ONLY be 20' off the ground. I can shoot them 5- 10 degrees of the horizon.

Try both. Put a pre-amp on each antennas BEFORE the combiner, and that should take care of the signal loss. One of the inline amps I saw, the DC power injector could power 3 such inline amps.

If you stack them vertical, maybe you could remove the coax connections and ladder-line connect them together, like you would a stack of rhombics? Not sure what the impedance would be at that point, but I bet somewhere here could give you an answer.

I would love to have the money right now for a tower and get my antennas up to 50'.

Try both. Put a pre-amp on each antennas BEFORE the combiner, and that should take care of the signal loss.

Unfortunately, that doesn't work. The noise of the amplifiers add, which eliminates the advantage of the decreased loss.

In order to add four antennas together with low loss you can use equal lengths of RG-6 with F connectors on one end and BNC on the other. Connect them to this: http://minicircuits.com/pdfs/ZFSC-4-175.pdf

The other way to add them it to make your own coaxial combiner. To do so, get three BNC TEE connectors. As above, use four equal lengths on RG-6 with F connectors on one end and BNC on the other. Have two antennas go to one TEE, the other two antennas to a second TEE. Use a quarter wavelength of 50 ohm coax to connect each TEE to a third TEE. Use 75 ohm coax between the third TEE and the preamp.

The length of the quarter wave matching lines would be 4 3/8" for channel 32, a frequency of 581 mhz. Slightly longer would work better below channel 32, slightly shorter for higher channels.

This is a BNC connector:
http://parts.digikey.com/1/parts/358900-conn-bnc-plug-rg-8x-lmr-240-112533.html
This is a BNC TEE
http://mouser.com/Search/Refine.aspx?Keyword=bnc+tee

It's this circuit without the balancing resistor: http://www.microwaves101.com/encyclopedia/Wilkinson_splitters.cfm

Don't you want to use 75 ohm BNC connectors with the ZFSC-4-175?

Don't you want to use 75 ohm BNC connectors with the ZFSC-4-175?

That is correct. The device has a 75 ohm impedenace BNC connector and requires a mating connector on the cable (or F to BNC adaptor). And, make sure its a 75 ohm, not a 50 ohm impedence BNC. They differ mechanically and electrically.

Cheers.

Here is the crazy projects I am thinking about.

1) Stack 4 - 91 XG's Vertically on the legs of the tower to try and get some Detroit coverage during the day. (

If youre going thru all that trouble, bite the bullet, go thru the learning curve, and get into antenna modeling with free 4nec2. Ken Nist already has the 91XG model posted, so a lot of work has already been done for you. :) Then you can tweak the model to find the best spacing distances and phasing lines without climbing up and down the tower, which can get old after a while, heh.

Fairly expensive STRIPLINE combiners have 0.2 to 1.0 dB of insertion loss (vice 6++ dB above),
but Lindsay Full UHF Band Couplers (2WCU1469 2-port, 0.2 dB loss and 4WCU1469 4-port, 0.2 dB loss)
are no longer available (maybe used???).
Fol. is summary of what I could find on-line. Call to see if they also stock full UHF Band:
http://www.avsforum.com/avs-vb/showthread.php?p=16072450
PS: IF it's small, it's a high-loss HYBRID transformer. Wilkinson low-loss Stripline Couplers are BIG.

Fairly expensive STRIPLINE combiners have 0.2 to 1.0 dB of insertion loss (vice 6++ dB above),
but Lindsay Full UHF Band Couplers (2WCU1469 2-port, 0.2 dB loss and 4WCU1469 4-port, 0.2 dB loss)
are no longer available (maybe used???).
Fol. is summary of what I could find on-line. Call to see if they also stock full UHF Band:
http://www.avsforum.com/avs-vb/showthread.php?p=16072450
PS: IF it's small, it's a high-loss HYBRID transformer. Wilkinson low-loss Stripline Couplers are BIG.

The Minicircuits splitter/combiner has 6 db loss only when used as a splitter. When used as a combiner the signals add with .2 to 1 db loss.

Yes, 75 ohm BNC's should be used with the Minicircuits combiner.

If you make your own with TEE connectors you'll need 50 ohm BNC's.

So does anyone have an opinion and or experience on a 91XG vs. HD-9032. Maybe a better candidate? I'm trying to get channel 19 which is about 50 miles.

Callsign Chan Network Dist(mi) Path NM(dB)
WBKI-DT 19 (34.1) CW 49.5 2Edge 14.8

I can't speak to the HD-9032, but the 91XG should pick it up OK. I get a ch 17 reliably from about 68 miles, with a 2Edge path and NM 13.7, and some blockage from trees. And a CM 7777 pre-amp.

So does anyone have an opinion and or experience on a 91XG vs. HD-9032. Maybe a better candidate? I'm trying to get channel 19 which is about 50 miles.

Callsign Chan Network Dist(mi) Path NM(dB)
WBKI-DT 19 (34.1) CW 49.5 2Edge 14.8I'd personally go with the 91-XG. I have seen a few posts here that tried both & prefer the 91-XG. I have very good results on channels 21(-2.1 nm) & 22(-13.2 nm) with mine. They are 85 & 99 miles away respectiviely. Both signals show activity 24/7, but generally only decode at night.

Please help!


So I dropped my cable for OTA. I bought a cheap, open box, antennas direct clearstream 1. I pointed it in the right direction. Bam - I get all the channels I'm supposed to get from my roof. I try to split it to run to the kitchen and guest room - I don't get 1/2 the channels. So i order a preamplifier - titan 2 7777. I get it all hooked up and it makes it worse. Why? Do I have to use special cable for the run from antenna to the power source? Is it something else? Help!

Please help!


So I dropped my cable for OTA. I bought a cheap, open box, antennas direct clearstream 1. I pointed it in the right direction. Bam - I get all the channels I'm supposed to get from my roof. I try to split it to run to the kitchen and guest room - I don't get 1/2 the channels. So i order a preamplifier - titan 2 7777. I get it all hooked up and it makes it worse. Why? Do I have to use special cable for the run from antenna to the power source? Is it something else? Help!

You likely have either

1) A defective pre-amp

or

2) A wiring or device usage error.

Eliminate the splitter first and make certain the pre-amp works. Verify it's set for combined input.

If it does, then examine where your power inserter is relative to the splitter. If the i9nserter is "downstream" from the splitter and the pre-amp is on the "other side" of the splitter, verify you are using a DC PASS splitter and that you have the cables hooked up correctly.

I did remove the splitter, and it still wasn't getting as many channels as without the preamp. "combined imput" is the default, but I opened it up and checked anyway. My splitter is downstream the power portion of the preamp.

Please help!


So I dropped my cable for OTA. I bought a cheap, open box, antennas direct clearstream 1. I pointed it in the right direction. Bam - I get all the channels I'm supposed to get from my roof. I try to split it to run to the kitchen and guest room - I don't get 1/2 the channels. So i order a preamplifier - titan 2 7777. I get it all hooked up and it makes it worse. Why? Do I have to use special cable for the run from antenna to the power source? Is it something else? Help!

Maybe all you need is a distribution amp instead of the splitter. I've had good results with the CM3414.

You likely have either

1) A defective pre-amp

or

2) A wiring or device usage error.3) Overload???????????? Can you go to www.tvfool.com & post your report link here?

Please help!


So I dropped my cable for OTA. I bought a cheap, open box, antennas direct clearstream 1. I pointed it in the right direction. Bam - I get all the channels I'm supposed to get from my roof. I try to split it to run to the kitchen and guest room - I don't get 1/2 the channels. So i order a preamplifier - titan 2 7777. I get it all hooked up and it makes it worse. Why? Do I have to use special cable for the run from antenna to the power source? Is it something else? Help!

Preamps can be overloaded. The 7777 is great for rural areas, but not in most cities.

The way to check if the 7777 is the right preamp is to look at the signal strengths on tvfool.com. You can post the results back here. You'll get more advice than you can handle.

philly_kid, post your TVFool. You may be overloading .


Edit: Heh, looks like a few beat me to the punch.

Also, do you mean to say you are getting channel 6 WPVI, with the Clearstream 1 ? If so, you are very close to the stations.

yes, the only problem I have w/channel 6 is during bad weather. I'm less than 10 miles to the majority of stations. I thought the preamp would mitigate the loss of signal from splitting...

here is the link to tvfool

http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3d7d4923d5c15812

here is the link to tvfool

http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3d7d4923d5c15812Yikes!!! Overload city!!! The only pre-amp that would work for you would be the HDP-269. With those signal strengths, I personally would avoid a pre-amp altogether & use a Winegard HD7694P antenna. It should easily power 2-3 sets with no amp. It should also pick up ABC 6 much better than the C-1, even though neither antenna is really designed for it.

The overload is too much even after splitting it 3-4 ways?

The overload is too much even after splitting it 3-4 ways?

Yes because the CM7777 boosts the signal by 20+dB which may be too much for the output stage. A CM3414 4-way distribution amp might work better since each output gets 8dB amplification and the input has some AGC I think.

John

Yes because the CM7777 boosts the signal by 20+dB which may be too much for the output stage. A CM3414 4-way distribution amp might work better since each output gets 8dB amplification and the input has some AGC I think.

The new Channel Master specs are poorly written. The CM3410, 3412 and 3414 each have 15 dB of amplifier gain, followed by internal splitter loss, and probably have a maximum input of 10dBmV with a 125 channel, flat input. God only knows what that means. In analog days, sometimes the maximum input/output figures were the power level at which the amplifier developed a recognized, unacceptable level of sync compression or cross modulation. Now it is more often the power level at which it develops some benchmark level of second or third order intermodulation distortion.

Some of the more reputable manufacturers seem to have standardized on using -40dBc 3rd order IMD as an engineering reference benchmark. An amplifier might be rated to develop -40 dBc of 3rd Order IMD with an input of one channel and an output of, say, 54 dBmV. From that, one can readily adjust for number of equal strength channels and number of amplifiers in a cascade, but unfortunately, off-air preamps almost never have equal strength inputs. There is always a differential in off-air signal levels, and weak signals will always get decimated by stronger signals in an amplifier at levels well below any published benchmark or reference overload levels. I can always bandpass filter off a single weak channel before preamplifying because I build headends that serve hundreds of customers, but most residential viewers cannot justify that expense.

Philly_kid is 8 miles from his problem, channel 6 transmitter, but he doesn't have a line of sight transmission path. He is not going to solve any problem he is having with an amplifier. He needs an antenna solution.

Yikes!!! Overload city!!! The only pre-amp that would work for you would be the HDP-269. With those signal strengths, I personally would avoid a pre-amp altogether & use a Winegard HD7694P antenna.

I wouldn't suggest a 7-69 antenna for channel 6 reception in a non line of sight situation. This is due to the increased possibility of multipath. For a new antenna I'd look at a Winegard HD7010 or larger. http://www.solidsignal.com/prod_display.asp?PROD=HD-7010

The cheapest solution would be to use a UVSJ to add a 2-13 VHF only such as the Antennacraft CS600 to the UHF only C1.
http://www.solidsignal.com/prod_display.asp?PROD=CS600
http://www.solidsignal.com/prod_display.asp?prod=UVSJ

I wouldn't suggest a 7-69 antenna for channel 6 reception in a non line of sight situation. This is due to the increased possibility of multipath.Agreed,

I only suggested the 7694 because of it's compact size, & the OP stated he is getting 6 OK now except during adverse weather.

I wouldn't suggest a 7-69 antenna for channel 6 reception in a non line of sight situation. This is due to the increased possibility of multipath. For a new antenna I'd look at a Winegard HD7010 or larger. http://www.solidsignal.com/prod_display.asp?PROD=HD-7010

The cheapest solution would be to use a UVSJ to add a 2-13 VHF only such as the Antennacraft CS600 to the UHF only C1.
http://www.solidsignal.com/prod_display.asp?PROD=CS600
http://www.solidsignal.com/prod_display.asp?prod=UVSJ

OK both of these options are reasonably priced and will require time for shipping. And in neither of these options I would need the pre-amplifier, correct? For the second option, I mount the CS600 on my roof, plug it and my C1 into the USVJ and split it somewhere downstream?

Which option is most likely to succeed?

Just got rid of my Directv setup and trying to get local channels for the first time in quite awhile. I have only ever used the basic analog antennas back in the day and am not sure what all I need.
My reception was never that great but that was before digital took over. Can anyone recommend a good antenna or antenna setup for me. Probably dont need anything to crazy since there arent a whole lot of channels to pick up, but I have no clue what I am looking at here.
I would like it to be able to give signal to an HTPC dual digital tuner and to a analog TV in the bedroom that I imagine I will get a convertor box for unless you guys no of a better option.

Here is my TV Fool. (http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3d7d497cb9e3133c)
Thanks in advance for the help guys.

I didn't realize this until it was pointed out to me, but my antenna is uhf only. I had my preamp set for combined uhf, vhf. While I was on the roof, I switched it back and forth but didn't seem to have much luck either way... Could this be part of the problem?

philly-kid

If you're trying to tune in VHF channels, of course.

I had a similar problem in reverse. My preamp was UHF only. By the time I discovered that, I had already ordered a new antenna.

philly-kid

If you're trying to tune in VHF channels, of course.

I had a similar problem in reverse. My preamp was UHF only. By the time I discovered that, I had already ordered a new antenna.

I'm getting my vhf channels fine w/o an amp. It's when I try to split it that I lose signals. I'm wondering if the preamp, amplifies the vhf signal even tho the antenna is uhf only, or if setting it to combined screws up the signals because the antenna is uhf only...

Are you certain you've got a splitter and not a diplexer?

BTW, you probably should list the problem channels....

I didn't realize this until it was pointed out to me, but my antenna is uhf only.
Yep, the C1 is worse than rabbit ears for your vhf-hi channels 6 and 12. Thats why I knew you were very close to the Manayunk hill.

I would try a 4 bay bowtie without any amp, and use a couple of quality (they will state the 3.5dbi loss on them) 2 way splitters.
The 4 bay bowtie will give you about 13 db gain, minus the 7 dbi for 2 splitters will put you back to about where the C1s gain is.
I would also return the CM7777 for a refund.

Were you using the C1 with the reflector ?

im using this as a splitter - http://www.goodmart.com/products/980788.htm

Im using 2 parts of the c1 - the disc and the rectangular cage behind it.

Which option is most likely to succeed?

I'd give the CS600 + C1 a 98% chance of success, the HD7010 99%.

I'd give the CS600 + C1 a 98% chance of success, the HD7010 99%.

I'll take those odds.

To get strong enough signals to split 3 ways?

I'll take those odds.

To get strong enough signals to split 3 ways?

If the C1 that you have now can be split three ways and you get WTXF on all three TV's your odds are very good.

Here are some more details. My antenna on the 4th floor roof, comes straight down to the second floor. I split it to the tv in that room and down to the basement where my "hub" is. All the coax from the house terminates there. From there, I split it again and go to two different rooms on the first and second floor.

Initially with a cheap splitter from the roof, I got most channels on that first tv I described on the second floor but nothing on the other two. Now with a better splitter, I'm getting everything on that second floor tv but still nothing on the other tvs. Does that make sense?

im using this as a splitter - http://www.goodmart.com/products/980788.htm
Based on what youre saying above, are you terminating the unused outlets on that 4 way splitter ?

My antenna on the 4th floor roof, comes straight down to the second floor. I split it to the tv in that room and down to the basement where my "hub" is.
OK, a good 2 way splitter should go there.

From there, I split it again and go to two different rooms on the first and second floor.
Then another good 2 way splitter should go there. Where are you using the 4 way splitter ?

My 08/10/2009 07:17 PM E-Mail to RCA:
I am trying to find the ANT2000. I have found that uppliers are stating that this item is "out of stock", "discontinued" or "no longer available". Is this item, or another Smart Antenna, still being manufactured? I want to use it with the RCA DTA800B converter box that I have.

8/12/2009 Reply from RCA:

Your concern is on getting the ANT2000.

Our apologies but we were recently informed by our headquarters that model ANT2000 has been pulled from the market, this is the only smart antenna model that RCA has and there's no information yet given if it will be reintroduced or if there will be a replacement model for it. You can visit www.rcaaccessories.com to check for the currently available antenna models in the stores. Our products are sold at our major dealers such as Walmart, Best Buy, Target or Radioshack. You may also search the internet for independent online retailers that may carry the product that you intend to buy.

Thank you.


Sincerely,

Reinel Tesoro
Customer Service

Based on what youre saying above, are you terminating the unused outlets on that 4 way splitter ?


OK, a good 2 way splitter should go there.


Then another good 2 way splitter should go there. Where are you using the 4 way splitter ?

Because I haven't gotten to getting a two way splitter yet, both my splitters are the 4 way i previously described.

My 08/10/2009 07:17 PM E-Mail to RCA:
I am trying to find the ANT2000. I have found that uppliers are stating that this item is "out of stock", "discontinued" or "no longer available". Is this item, or another Smart Antenna, still being manufactured? I want to use it with the RCA DTA800B converter box that I have.

8/12/2009 Reply from RCA:

Your concern is on getting the ANT2000.

Our apologies but we were recently informed by our headquarters that model ANT2000 has been pulled from the market, this is the only smart antenna model that RCA has and there's no information yet given if it will be reintroduced or if there will be a replacement model for it. You can visit www.rcaaccessories.com to check for the currently available antenna models in the stores. Our products are sold at our major dealers such as Walmart, Best Buy, Target or Radioshack. You may also search the internet for independent online retailers that may carry the product that you intend to buy.

Thank you.


Sincerely,

Reinel Tesoro
Customer Service

http://www.avsforum.com/avs-vb/showthread.php?p=16495045&highlight=rca+smart+antenna#post16495045

http://www.avsforum.com/avs-vb/showthread.php?p=16497427&highlight=buy#post16497427

Because I haven't gotten to getting a two way splitter yet, both my splitters are the 4 way i previously described.

Avoid using a splitter with a greater number of ports than you need. You will incur the splitter's greater loss regardless of whether you needed to.

philly_kid,

You have a lot of cable distance to overcome between the roof above the fourth floor and the basement distribution location. Between that and having two 4-way splitters produces at least 16dB loss to the last two televisions. You'll gain 8dB by using two 2-way splitters.

Make sure they will pass at least 700MHZ.

having two 4-way splitters produces at least 16dB loss to the last two televisions
Plus extra if the unused ports arent terminated. :eek:

My 08/10/2009 07:17 PM E-Mail to RCA:
I am trying to find the ANT2000. I have found that uppliers are stating that this item is "out of stock", "discontinued" or "no longer available". Is this item, or another Smart Antenna, still being manufactured? I want to use it with the RCA DTA800B converter box that I have.

8/12/2009 Reply from RCA:

Your concern is on getting the ANT2000.

Our apologies but we were recently informed by our headquarters that model ANT2000 has been pulled from the market, this is the only smart antenna model that RCA has and there's no information yet given if it will be reintroduced or if there will be a replacement model for it. You can visit www.rcaaccessories.com to check for the currently available antenna models in the stores. Our products are sold at our major dealers such as Walmart, Best Buy, Target or Radioshack. You may also search the internet for independent online retailers that may carry the product that you intend to buy.

Thank you. Sincerely, Reinel Tesoro, Customer Service
You might have to look for a used or refurbished ANT2000:
http://www.solidsignal.com/prod_display.asp?prod=ANT2000-REFURB&gclid=CLmHufWsoZwCFRFWagodqHF0dw

or DX Antenna DTA-5000 Smart Antenna (aka Sylvania, aka Funai, et. al.):
http://www.amazon.com/Funai-Sylvania-Smart-Digital-Antenna/dp/B000EHYFPU
http://athome-products.com/dta-5000.html

Comparison tests and interior photos are here:
http://imageevent.com/holl_ands/smart

Antennas Direct was working on a UHF Smart Antenna (funding from NAB).
Still no info from A-D re when (if???) they will release to production....

Antennas Direct was working on a UHF Smart Antenna (funding from NAB).
Still no info from A-D re when (if???) they will release to production....

Not going to happen any time soon (if at all). That should have been obvious from the report you read.

No TV sets with an SA interface and a cluster-fark of incompatible, non-conforming interface implementations in cheap boxes that are purpose-built to be obsolete. As indicated by JER's post on one of the other forums, there's no point in dropping private money into any production until there's a real market, especially in an over-all crappy economy.

The system, when connected to a compatible converter box, works great. The SA electronics, by itself, could make rotors and separate pre-amps obsolete.

John Ross (A-D Design Engineer) posted fol. re Smart Antenna I/F problems:
http://www.digitalhome.ca/forum/showthread.php?p=967868
A-D reported that incompetent EIA/CEA-909 implementations in most
CECBs with Smart Antenna I/F are an (exaggerated?) problem:
http://www.nabfastroad.org/NAB_Final_Report_Rev_Public2.pdf
PS: Which is probably solvable with Firmware updates to CECBs.....

I still believe there's a market for a Smart Antenna I/F Controller Box that
could select between multiple EXTERNAL antennas pointed in different directions.
EIA/CEA-909 would be one way to control it...responding to IR commands
or other control interfaces (most manu's seem to have one) would be an
alternative configuration.

Here are the problems:

Name one TV set that has a smart antenna interface.

How many CECB manufacturers are likely go back and "fix" potentially thousands of boxes that don't work to the 909/A standard? These were devices that sold wholesale for $20 - $30 in quantity.

Who's going to test each existing CECB model (including different rev levels of firmware) to see if a potential customer's device will work?

If the CECB doesn't work right, who's going to pay for all the additional work to adapt the SA device to non-compliant controllers so they can be made to work?

I agree that there is certainly a market to be had, however, the problem is both lack of a coherent current market and zero future market unless the TV set manufacturers get aboard.

I still believe there's a market for a Smart Antenna I/F Controller Box that could select between multiple EXTERNAL antennas pointed in different directions.
Absolutely, I'd buy one, if it was antenna manufacturer independent, good quality and at a reasonable price.

Should I worry about getting any type of antenna lighting protection? Was reading the manual to my new antenna and they were talking about it and I want to make sure my TV and Computer are safe. Is this anything to worry about and if so what are the recommendations? I have it mounted to my rough on my old directv mounting stand.

okfireman,

I think you meant to say it is roof mounted? If so, take a look at what happened to my roof mounted antenna after a lightning strike. Direct hit, and there was collateral damage to other stuff in the house even though I had it grounded. But the TV and entertainment systems were unharmed.

http://www.avsforum.com/avs-vb/showthread.php?p=16719970#post16719970

You're going to have to make the call for yourself. Good luck!

If you're surrounded by much taller trees, does having a ground to the antenna matter?

Doesn't lighting find the highest nearby object?

It's probably a local code requirement....and if you suffer lightning damage, the insurance
company can use it as justification for NOT PAYING....

PS: Static electricity can build up on a low mounted antenna due to the WIND and can cause
damage to electrical gear at much lower voltages than associated with lightning:
http://www.kilty.com/t_elec.htm
http://www.concentratemedia.com/innovationnews/accioenergyannarbor0063.aspx
http://en.wikipedia.org/wiki/Atmospheric_electricity

Yes I meant its roof mounted.
No large trees around anywhere.
I live in a small town with pretty leanent codes so I doubt its a code but you never know.
Are there any recommendations on what to do to help reduce the chance of lighting damage or what should I do as a preventative measure?

re there any recommendations on what to do to help reduce the chance of lighting damage or what should I do as a preventative measure?

Here is a good tutorial on the subject:
http://www.mikeholt.com/newsletters.php?action=display&letterID=220

Basically need to drive a ground rod and connect it to the antenna. Then bond ground rod to building electrical system. What you are trying to do is drain off any charge on the antenna and by bonding minimize voltage difference between antenna and other metallic parts of the building.

As far as lightning being attracted to the highest object that is true to an extent. We are a long way off the road and have our own step-down transformer before aerial plant goes underground the last couple of hundred feet. During a storm transformer took a direct hit, even though nearby trees are much taller. Exploded the porcelain lightning arrester on the transformer and took out a bunch of electronics. When utility was repairing transformer the crew mentioned the most dangerous place to be during a storm is at the edge of an open field. As charge builds up it tends to get dragged to objects that reduce path length. Homes are typically at the end of clearing and metallic mast makes a great conductor.

Having endured it once I take lightning protection very seriously now.

Grounding wire from antenna to ground, in accordance with NEC recommendations,
which may be modified by your local zoning authorities. (NEC=National Electric Code)

You probably can tie into the existing ground system for the Sat Dish if it was installed correctly:
http://www.sadoun.com/Sat/Installation/Grounding.htm
http://www.dbsinstall.com/diy/Grounding-2.asp
[Navigate within this website for additional info.]

NEC required "grounding block" has a spark gap to discharge moderately high voltages:
http://www.radioshack.com/product/index.jsp?productId=2150592
For additional protection from lower voltage static electricity, see fol:
http://www.avsforum.com/avs-vb/showthread.php?p=8591196

Lightning is a tricky beast. Tentacles of ionization reach upward from all manner of objects, while other tentacles reach downward out of the clouds. The first tentacles to connect complete a circuit and lightning follows.

The tentacles from taller objects start out marginally closer to the cloud layer, but that doesn't mean lightning always strikes the tallest object. Some tentacles start earlier and/or grow faster than others, and an object that had a fast tentacle in one storm may have slow tentacles in other storms. It's all very chaotic.

Is this either a: Small multi-directional, medium multi-directional, large multi-directional, small directional, medium directional, or large directional? What are the miles for VHF/UHF/FM?

Is this either a: Small multi-directional, medium multi-directional, large multi-directional, small directional, medium directional, or large directional? What are the miles for VHF/UHF/FM?

Medium directional.

Take whatever mileage Radio Shack said and divide it in half. The VU-90 was rated by them at 90 miles on VHF and some lesser amount on UHF.

Edit: Here are the VU90 specs:

VU-90XR VHF/UHF/FM Antenna
(150-2152) Specifications Faxback Doc. # 31760

Average FM Gain: .................................................. 1.0 dB

Low Band Gain: .................................................... 3.7 dB

High Band Gain: ................................................... 5.9 dB

UHF Band Gain: .................................................... 6.4 dB

Median Avg. F/B Ratio:
VHF Low Band: .................................................... 12.0
High Band: ....................................................... 12.0
FM: ............................................................ .. 11.0
UHF: ............................................................ . 16.0

Average Half-Power Beam Width:
Ch. 2-6: ................................................... 66 degrees
Ch. 7-13: .................................................. 42 degrees
FM: ........................................................ 68 degrees
UHF: ....................................................... 43 degrees

Element Width (Avg.): .................................... 5.5 to 6.0 Feet

Boom Length: ................................................... 80 Inches

Weight: ......................................................... 5.7 lbs.

Specifications are typical; individual units might vary. Specifications
are subject to change and improvement without notice.


(IR/EB 1/23/97)

Today reception strength is cycling 0-75% continuously, up and down
If it is multipath, why no problem for the last week until today?

Today reception strength is cycling 0-75% continuously, up and down
If it is multipath, why no problem for the last week until today?

Might be interference due to atmospheric conditions. With no information about your situation, we can only guess.

Keep in mind that the "signal" meter displays the quality (decodability/lack-of-data-errors) of the date being received, not the strength of the signal. This quality can be degraded by a variety of things including interference and multi-path besides a lack of raw signal power.

Might be interference due to atmospheric conditions. With no information about your situation, we can only guess.
http://www.dxinfocentre.com/tropo.html

Absolutely, I'd buy one, if it was antenna manufacturer independent, good quality and at a reasonable price.

I Tivo everything on a HR10-250 and my stations are in multiple directions so I needed a way to aim the antenna at the appropriate time.

Well, It's not as smart as I would like, but here's how I made my antenna smarter than most. I started with a DB8 antenna and a Channel Master CM 9521A rotator. The rotator will aim to any pre-programmed direction via an IR remote.

Then I picked up a Palm Treo on eBay and added Wawa software by Novii (http://www.novii.tv/pocketpc/wawa/). The Palm is capable of sending and receiving IR and the software is designed to store IR signals and replay them at a designated time.

So now, when I do a Season Pass that requires the antenna, I program the Palm to point the antenna to the correct station at the correct time and day. :)

I Tivo everything on a HR10-250 and my stations are in multiple directions so I needed a way to aim the antenna at the appropriate time.

Well, It's not as smart as I would like, but here's how I made my antenna smarter than most. I started with a DB8 antenna and a Channel Master CM 9521A rotator. The rotator will aim to any pre-programmed direction via an IR remote.

Then I picked up a Palm Treo on eBay and added Wawa software by Novii (http://www.novii.tv/pocketpc/wawa/). The Palm is capable of sending and receiving IR and the software is designed to store IR signals and replay them at a designated time.

So now, when I do a Season Pass that requires the antenna, I program the Palm to point the antenna to the correct station at the correct time and day. :)

Very nice. Auto rotor, which many have inquired about over the years.

Here are the problems:

Name one TV set that has a smart antenna interface.

How many CECB manufacturers are likely go back and "fix" potentially thousands of boxes that don't work to the 909/A standard? These were devices that sold wholesale for $20 - $30 in quantity.

Who's going to test each existing CECB model (including different rev levels of firmware) to see if a potential customer's device will work?

If the CECB doesn't work right, who's going to pay for all the additional work to adapt the SA device to non-compliant controllers so they can be made to work?

I agree that there is certainly a market to be had, however, the problem is both lack of a coherent current market and zero future market unless the TV set manufacturers get aboard.

It's going to take a coordinated effort from HDTV & antenna manufacturers, which I expect to see at some point in the near future.

I Tivo everything on a HR10-250 and my stations are in multiple directions so I needed a way to aim the antenna at the appropriate time.

Well, It's not as smart as I would like, but here's how I made my antenna smarter than most. I started with a DB8 antenna and a Channel Master CM 9521A rotator. The rotator will aim to any pre-programmed direction via an IR remote.

Then I picked up a Palm Treo on eBay and added Wawa software by Novii (http://www.novii.tv/pocketpc/wawa/). The Palm is capable of sending and receiving IR and the software is designed to store IR signals and replay them at a designated time.

So now, when I do a Season Pass that requires the antenna, I program the Palm to point the antenna to the correct station at the correct time and day. :)

...and when you want to record two programs in different directions?

...and when you want to record two programs in different directions?

That hasn't been an issue yet but I'd pick the one I like best and hope I get lucky on the other one.

It's probably a local code requirement....and if you suffer lightning damage, the insurance
company can use it as justification for NOT PAYING....

PS: Static electricity can build up on a low mounted antenna due to the WIND and can cause
damage to electrical gear at much lower voltages than associated with lightning:
http://www.kilty.com/t_elec.htm
http://www.concentratemedia.com/innovationnews/accioenergyannarbor0063.aspx
http://en.wikipedia.org/wiki/Atmospheric_electricity

I'll say. I was burning out surge protectors entirely too often. When I put up my OTA antenna I discovered the satellite installer hadn't put in any grounding at all. :eek:

Even if the work has been done by a 'professional', it doesn't hurt to inspect it.

So now, when I do a Season Pass that requires the antenna, I program the Palm to point the antenna to the correct station at the correct time and day.
Alright. Thats pretty ingenious ! Where theres a will, theres a way, heh. A remote with a timer.

..and when you want to record two programs in different directions?
Two antenna setups ? (didnt say it was easy, heh)

Might be interference due to atmospheric conditions. With no information about your situation, we can only guess.

Keep in mind that the "signal" meter displays the quality (decodability/lack-of-data-errors) of the date being received, not the strength of the signal. This quality can be degraded by a variety of things including interference and multi-path besides a lack of raw signal power.

I am 65 mi away, using Radio Shack VU 160
Last night the signal was 93-100%, still there was persistent audio and video hiccups.
I get a poor signal pointing at the station 353 degrees (TV Fool) and much better if pointing at 5 degrees (compass).
The cycling (0-75) signal strength occurs during the daytime, but some days the signal is stable.

It's going to take a coordinated effort from HDTV & antenna manufacturers, which I expect to see at some point in the near future.

Ken,

You're way more optimistic than I am.

The CEA published the spec but their own members don't adhere to it.

Reminds me of the comment that a Best Buy buyer made regarding having their store-branded TVs implement the standard <paraphrased>: "Hell, we can't even get our vendors to put the damn holes for the mounts in the right place on the rear panel!"

...

So I went with the 91xg for the CW at ~50 miles. Got it yesterday and will mount it tomorrow on the same mast as the 4228 that points at the rest of my stations at 15 miles. Any advice on the setup. Right now the 4228 is pretty much at the top of the mast which is eave mounted. Everything comes in great now so I'm tempted to leave it and mount the 91xg under it. Will it matter?

I get a poor signal pointing at the station 353 degrees (TV Fool) and much better if pointing at 5 degrees (compass).
TVFool displays both the True and Magnetic headings. So if using a compass, use the Magnetic headings. Keep in mind, most cheap compasses havent been properly compensated and keep it some distance from your body and metal surfaces.
The cycling (0-75) signal strength occurs during the daytime, but some days the signal is stable.
Most likely the heating of the earth in front, causing fading. http://www.hdtvprimer.com/ANTENNAS/fixes.html

TVFool displays both the True and Magnetic headings. So if using a compass, use the Magnetic headings. Keep in mind, most cheap compasses havent been properly compensated and keep it some distance from your body and metal surfaces.

Most likely the heating of the earth in front, causing fading. http://www.hdtvprimer.com/ANTENNAS/fixes.html

Thanks for the info....much appreciated

A question for anyone in the group that might know: What affect does foliage have on reception? My thinking suggests that density of foliage, path length through it, type (conifer vs deciduous trees or dense shrubs for example), size and orientation of leaves, frequency (UHF is more affected than VHF), weather conditions (i.e. wet leaves from rain cause more problems that dry leaves?). Anything else? Are there any modeling studies out there that give guidelines on anticipated loss for path lengths through certain types of foliage?

I was wondering about this as I drove around town contemplating purchasing a house and saw all the homes with trees around them, some of which were blocking views of our local antenna farm. Makes me think adding trees and plants into the decision matrix might be prudent. They could screen an antenna from public sight if there's a lot of grief over OTA antennas but at the same time negatively affect reception. Fortunately, I live in CO so its not like I'd have a long path through it. Still, it made me curious. Thoughts anyone?

What affect does foliage have on reception? Are there any modeling studies out there that give guidelines on anticipated loss for path lengths through certain types of foliage?

Thoughts anyone?

hdtv primer has a few things to say about trees and diffraction:

http://www.hdtvprimer.com/ANTENNAS/glossaryR.html#trees

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

The changing signal thru trees moving in the wind is a type of dynamic multipath problem which is much harder for a tuner to correct than a static multipath problem, as from a secondary signal reflected from a building. The more of the limited correction ability of the FEC (forward error correction) system that is used to correct increasing error rates (BER), the less that is available to correct errors from weak signals.

hdtv primer has a few things to say about trees and diffraction:

The changing signal thru trees moving in the wind is a type of dynamic multipath problem which is much harder for a tuner to correct than a static multipath problem, as from a secondary signal reflected from a building. The more of the limited correction ability of the FEC (forward error correction) system that is used to correct increasing error rates (BER), the less that is available to correct errors from weak signals.

Hmmm, that's an interesting thought rabbit. Could make for challenging reception. I guess the take away from this is: Avoid having foliage within line of sight.
Cheers.

Some info re Attenuation through Trees:
http://www.its.bldrdoc.gov/isart/art99/slides99/vog/vog_s.pdf
http://www.micropath.net/pages/pathanal/foliage.htm
http://awapps.commscope.com/search/bn_TP-100328-EN.aspx

Are there any rules against offering an antenna for sale on this forum? Looked in the FAQ but couldn't find anything.

Are there any rules against offering an antenna for sale on this forum? Looked in the FAQ but couldn't find anything.

Go here: http://www.avsforum.com/avs-vb/vbclassified.php

From the www.sutrotower.com website .... for those hoping to see improved digital coverage in the Bay Area.

The eleven television stations at Sutro Tower currently broadcast in both the analog and digital format. The Sutro Tower analog antennas are currently located at the top of the transmission tower and the interim digital antennas are located at a lower elevation on the tower, a less optimal position for best coverage of the service area. Currently, there is no back-up facility for digital transmission should maintenance be required on the primary antenna. The conversion project will locate the primary digital antennas in a more favorable position at the tower top, and provide back-up facilities for digital transmission.

A new digital auxiliary antenna will be installed between the 380 ft. and 560 ft. elevation on the tower. It will consist of two identical antennas each serving 5 stations. A third back-up antenna will be installed at the 180 ft. level for the remaining station.

The existing analog antennas at the top of the tower will be removed and replaced with six new digital main antennas. One will serve four stations, one will serve three stations and the other four will serve one station each.

Combining equipment to facilitate main and auxiliary antenna sharing will be installed. A new roof top enclosure will be constructed to accommodate the combining equipment for the new system.

The existing interim digital antenna will be removed.

The tower structure will be reinforced in selected location to accommodate the new antennas and to upgrade the structure to current wind and seismic codes for essential facilities.


Work, which began in mid-January 2009, is anticipated to take approximately 8-10 months.
Sequence of work will be as follows:

1.Reinforce tower to accommodate new digital auxiliary antennas--Complete
2.Construct roof top equipment enclosure--Complete
3.Install digital auxiliary antennas--Complete
4.Reinforce tower to accommodate new digital main antennas--Complete
5.Remove old KGO, KBCW, and KOFY analog antennas from South mast--Complete
6.Install new KGO and KBCW digital antnenas on South mast--Complete
7.Remove old KTVU, KRON, and KPIX antennas from West mast--Complete
8.Install new lattice tower to 918 feet on West Mast--Complete
9.Install new KTVU, KRON, and KPIX digital antenna on West mast--Scheduled week of 8/24
10.Install new KOFY digital antenna on West mast--Scheduled week of 8/24
11.Remove old KQED, KMTP, KFSF, and KOIT analog antennas from North mast--Scheduled week of 9/28
12.Remove old North mast support down to 792 feet--Scheduled week of 9/28
13.Install new KQED, KMTP, KCNS, and KCSM digital antenna to top of new North mast--Scheduled week of 10/5
14.Install new KFSF digital antenna on side of new North mast--Scheduled week of 10/19
15.Re-install KOIT (FM) antnena on side of North mast--Scheduled week of 10/19
16.Remove temporary KOIT antenna--Scheduled week of 10/26
17.Test and begin operation of new digital antennas for all stations--Scheduled week of 10/26
18.Remove old analog auxiliary antennas
19.Remove old interim digital antennas

From the www.sutrotower.com website .... for those hoping to see improved digital coverage in the Bay Area.


I grew up in the Bay Area (Cupertino 50s-70s) and remember the brouhaha that went on over its construction. My grandma lived in SF (Mission District) and we'd often drive by there on the way to/from visiting. I always thought it was cool. But then, being a radio/electronics geek I think all antennas and aluminum forests are cool. :D
Cheers.

I live in Eugene, Oregon.
I am having antenna issues.

We basically have two main transmitting hills, one 6 miles away at 9 degrees.
The other 4 miles away at 217 degrees.
There are hills and trees.
My house sits below street level but the roof mounted outdoor antenna, sits at about street level.
Currently using a Terrestrial DB2 mounted on a J-Type mast.

After the conversion, I lost the signal on my CBS station broadcasting on VHF channel 13 (217 degree heading)
Initially I thought it was because my DB2 wouldn't pick up VHF until today I realized that our ABC channel 9 is using VHF 9.(9 degree heading) I get an excellent signal from it and the NBC station at this heading.
The FOX station is at the 217 degree heading as well and I get about 70 on my antenna signal meter. Not as good as I would like but we deal with it.

I have been reading antenna info about the CM 4228HD because I thought it was a VHF/UHF issue until today.
Now I am really confused and could use some suggestions on What antenna.



Thanks!

I need a uni-directional solution for a mountainous area. I am only 20 miles from the towers needed to receive all the networks 2.1 - 21.1. I tried a xg91 before realizing I would need more of a VHF type antenna. After carefully pointing it, I only had marginal signal levels and just 2 channels. Could the 2-edged path be the problem? After reading through this forum I think I might get by with a Winegard HD7694P and a CM7777. Before I order them I am hoping to get some input from the experts around here to find out if something else might be more appropriate. Thanks in advance.

Here is my TV Fool: tvfool.com/?option=com_wrapper&Itemid=29&q=id%3dd5a0991ab1d1c5

After reading through this forum I think I might get by with a Winegard HD7694P and a CM7777.


No, you won't. You have channels 2 and 5 which are low band VHF stations. The HD7694P is not a low band antenna.

Your stations are in two directions. Do you want a rotor or a custom designed combiner?

Now I am really confused and could use some suggestions on What antenna.

If you want one antenna plan on a rotor.

If you don't want a rotor you need two antennas and a combiner. It's best if both antennas are rated for VHF/UHF.

There's a second PBS in a third direction. Do you want it too?

Thanks Tower Guy - I only need the stations from one direction(140). The others are duplicates. Channel 2 is the strongest and I don't need 5. Do you think I still would need a separate low band antenna, and if so should I just pair it with the xg91 and 7777? Would that be overloading from that close? Thanks again.

Channel 2 is the strongest and I don't need 5
You're pulling in 2 with a XG91, 2edge, 20 miles out?

I only need the stations from one direction(140).

OK, add a Y5-2-6 or CS600 to the 91XG and use the 7777 preamp or a Winegard AP2870 to add them togther.

Thanks for the advice. I will be ordering the CS600 and 7777.

Take a look at the Channel Master 3020 and pair it with the 7777.

NOTE: There is a member that is an hour South of me and I, who use the CM3020 for 2-edge, 60+ mile reception and find it does well.

So I got the XG91 mounted. It's a lot bigger than I thought it would be. I reduced my cable run through the attic so it's at about 20 ft. I'm trying for just WBKI (RF19) at 50 miles and combining it with a jointenna with everything else. I get a steady signal straight from the antenna to the hdhomerun, 60% signal strength and 75% signal quality. Once I combine the signals with the jointenna and split the signal for the two tuners, I get about 50% for both and no lock. At night I'm looking at it right now and I have a little over 60% and a lock. So I'm right at the cusp and it seems I have enough signal at the antenna with a high enough S/N to use a preamp, maybe a CM 7777. What do you think? It will only amplify the XG91 so I'm hoping it won't overload although I do see channel 26 on the back side at fairly high levels. Just out of curiosity, besides splitting the signal, are low noise and placement the only thing that usually separate a preamp from an distribution amplifier? Also, is it possible the CM 7777 has lower noise than the hdhomerun's internal gain and the noise floor be set by the cm 7777 and possibly be lowered? Am I totally off base? I have no idea what the noise level for the hdhomerun is.

I also noticed that if I swung my CM 4228 around it got a stronger signal from channel 19 although it fluctuated a bit while the 91XG held at nearly the same values. I was reading that the XG91 was more consistent with the signal in terms of getting a lock. Is this true? I was started to regret purchasing the XG91 over another 4228.

So I'm right at the cusp and it seems I have enough signal at the antenna with a high enough S/N to use a preamp, maybe a CM 7777. What do you think?

I think the the 7777 has more gain than you need. The HDP-269 has less gain, roughly the same noise figure, and is far more resistant to overload.

The HDP-269 will improve your signal in many ways;

Eliminate the loss of 20' of RG-6.
Minimize any impedance mismatch losses.
Overcome the loss of the Jointenna.
Overcome the loss of the splitter.
Eliminate the losses of the jumper cables.
Have a lower noise figure than your tuner.

I was started to regret purchasing the XG91 over another 4228.
For RF channel 19, the Winegard PR-8800 would have been the better choice. http://www.hdtvprimer.com/ANTENNAS/comparing.html

For RF channel 19, the Winegard PR-8800 would have been the better choice. http://www.hdtvprimer.com/ANTENNAS/comparing.html

Yeah, I saw that. Unfortunately Ant Online's return policy is essentially non-existent. Probably should have went with the Winegard and saved some money as well. I ordered the HDP-269 today and hopefully it will be here tomorrow and we'll see if everything works regardless. Is there anything to this notion that the XG91 will provide a more stable signal? Is this only valid close to the antenna? I wonder if the backside of an 8-Bay would have given me problems in the event of amplification, even with the HDP-269.

The HDP-269 will improve your signal in many ways;

Have a lower noise figure than your tuner.

Just out of curiosity, when you mentioned this are you basing this on a noise figure you know for the hdhomerun or are you assuming in general, a good preamp will have lower noise in the amplification than any tuner. Also thanks for the advice.

Just out of curiosity, when you mentioned this are you basing this on a noise figure you know for the hdhomerun or are you assuming in general, a good preamp will have lower noise in the amplification than any tuner. Also thanks for the advice.
Although RF CHIP manufacturers are making Noise Figure claims as low as 5 dB,
it probably doesn't include some of the essential stuff NOT in the chip.

Here are some ACTUAL Noise Figure measurements:
http://www.digitalhome.ca/forum/showthread.php?p=974143
http://www.digitalhome.ca/forum/showthread.php?p=879273

The fol. chart should help compare the improvement w and w/o Preamp:
http://www.digitalhome.ca/forum/showthread.php?p=888368
The example assumes a (well above average) 6 dB N.F. Tuner. If it was connected
DIRECTLY to the antenna, Total System N.F. = 6 dB and if at the
End of a 6 dB loss cable, Total System N.F. = 12 dB (simple addition).

With a Preamp and 6 dB of "Gross Transmission Loss" after the Preamp (incl coax & splitters):
Low-gain, high overload HDP-269, Total System N.F. = 4.5 dB.
High-gain, low overload CM-7777, Total System N.F. = 3.25 dB.

When a mast-mounted Preamp is added, the calculation is fairly complex, since
the loss AFTER the Preamp (incl Tuner N.F.) is REDUCED by the Preamp Gain. So
high gain preamps would presumably be preferred....IFF you can maintain SFDR
(Spurious Free Dynamic Range)...better known as DON'T OVERLOAD IT:
http://imageevent.com/holl_ands/files/ota

Which is why we keep saying BEWARE OF HIGH-GAIN PREAMPS IN URBAN/SUBURBAN AREAS....
And in the above example, the CM7777 was only 1.25 dB "better" Total N.F....
possibly at the expense of 10-20 dB higher Intermod Noise.....

Although RF CHIP manufacturers are making Noise Figure claims as low as 5 dB,
it probably doesn't include some of the essential stuff NOT in the chip.

Here are some ACTUAL Noise Figure measurements:
http://www.digitalhome.ca/forum/showthread.php?p=974143
http://www.digitalhome.ca/forum/showthread.php?p=879273

The fol. chart should help compare the improvement w and w/o Preamp:
http://www.digitalhome.ca/forum/showthread.php?p=888368
The example assumes a (well above average) 6 dB N.F. Tuner. If it was connected
DIRECTLY to the antenna, Total System N.F. = 6 dB and if at the
End of a 6 dB loss cable, Total System N.F. = 12 dB (simple addition).

With a Preamp and 6 dB of "Gross Transmission Loss" after the Preamp (incl coax & splitters):
Low-gain, high overload HDP-269, Total System N.F. = 4.5 dB.
High-gain, low overload CM-7777, Total System N.F. = 3.25 dB.

When a mast-mounted Preamp is added, the calculation is fairly complex, since
the loss AFTER the Preamp (incl Tuner N.F.) is REDUCED by the Preamp Gain. So
high gain preamps would presumably be preferred....IFF you can maintain SFDR
(Spurious Free Dynamic Range)...better known as DON'T OVERLOAD IT:
http://imageevent.com/holl_ands/files/ota

Which is why we keep saying BEWARE OF HIGH-GAIN PREAMPS IN URBAN/SUBURBAN AREAS....
And in the above example, the CM7777 was only 1.25 dB "better" Total N.F....
possibly at the expense of 10-20 dB higher Intermod Noise.....


I have had the best results by using a indoor distribution amp instead of a preamp. My antenna is in the attic so I just ran an ac drop cord from an outlet to near the antenna to power the amp. I ran the 300 ohm wire with 3 twist per foot a short distants to the amp. On the input of the amp I used a 300 to 75 ohm [slip on like are used on the back of the TVs to connect 300 one wire] transformer. From the amp down to the tv I used 75 ohm. The distribution amp are built to carry strong signals.

Although RF CHIP manufacturers are making Noise Figure claims as low as 5 dB,
it probably doesn't include some of the essential stuff NOT in the chip.

Here are some ACTUAL Noise Figure measurements:
http://www.digitalhome.ca/forum/showthread.php?p=974143
http://www.digitalhome.ca/forum/showthread.php?p=879273

The fol. chart should help compare the improvement w and w/o Preamp:
http://www.digitalhome.ca/forum/showthread.php?p=888368


Awesome. Thanks for the links. I've been looking for this information. I didn't realize the noise on the tuner was so high. Silicon Dust responded to me with this for their signal quality measurement which I presume to be S/N.

8VSB: 50% = 16dB, 100% = 30dB

Am I to assume that with the hdp-269 I may gain ~3dB on the low end from the noise of the hdp-269 being lower and 12 dB on the high end from the gain for an overall gain of 15 dB in S/N, and if so can this figure be added to the 16 dB, assuming I'm getting a 50% reading?

Does anyone know if there is a specific antenna or brand in general that is more robust (weather/wind resistant) than most of the rest?

Also, why are Blonder Tongue antennas so much more expensive than most?

I decided to give this a try and I purchased the Phillips SDV2740 indoor antenna.

When I do an "auto program" (or scan). It only finds two channels.

Univision 26-1, and Telefutura 26-2.

And the signal is really bad. Only 3-5 bars (out of 10).

I don't know if this the correct thread to ask. But I want to find out if people purchased the same antenna and what they did to fix it.

My TV is Samsung LN46A630.

Tuners: NTSC / ATSC

Go to TVFOOL.com and use the signal analysis tool button to get an availability report.
Post it here and people will be able to help you out on your reception problems.
:)

I'm looking for antenna recommendations for pulling in WRGB(6), which is about 65 miles away. I currently have an old Taco antenna in my attic that grabs a watchable signal about 30% of the time. Is there anything out there that can do better or am I already doing about as well as I can hope? This antenna appears to be a 9-element Yagi. It has a 106-inch boom and the elements are of various sizes with the longest at ~110-inches. It is a very odd antenna with loops in the middle or at the ends of some of the elements. Prior to the switch, the best reception was on Ch2. It did OK on 9, but poorly on 11 and 13, so I assume the antenna was optimized for Low-VHF.

Ideally, I want an antenna that can pull in 6-13, since I have stations on 6,7,11,12, and 13. Since this is for an attic mount, I really can't go any bigger than the existing antenna. I'd even like to be a bit smaller, which seems possible since I don't need gain on 2-5 (longer wavelengths). Any suggestions?

In addition to the 6-13 VHF antenna I mentioned above, I am also considering a YA-1713 to pull in channels 7, 11, 13 from New York City (65 miles away and 180 degrees from the Albany stations of 6, 7, 12). I would most likely connect this with an A-B switch feeding into a CM7777 pre-amp (where it is combined with my UHF antenna), but I was curious if there would be any way to connect in multiple channels from each antenna using a jointenna or something similar?

Hi Semi,
YOu may have better luck posting in the Albany thread.
There are a couple of people in poughkeepsie over there having issues with WRGB 6.
Some have reliable signals now.
Have you looked at your TVFOOL report, to see what you can expect to receive?

Go to TVFOOL.com and use the signal analysis tool button to get an availability report.
Post it here and people will be able to help you out on your reception problems.
:)

This is my report based on TV FOOL

http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3d8ecdf8713064af

I live in an apartment complex, 1st floor (of three stories). My room window and balcony in the living room face WEST.

This is my report based on TV FOOL

http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3d8ecdf8713064af

I live in an apartment complex, 1st floor (of three stories). My room window and balcony in the living room face WEST.

The channel you are getting is northeast of you ... strange you wouldn't do better than that with all of those strong signals in the air.

At the least (and I'm sure you've tried already), I'd rotate the antenna a quarter turn and try again.

Metal and plaster used in construction, and the new low heat transfer windows, often are very effective in blocking signals. The next thing I'd try is sticking the antenna out the window and scanning again ... perhaps not permanently, but for a test.

Do you know if you have neighbors with good signals? What is their technique?

Good luck!

Hi Semi,
YOu may have better luck posting in the Albany thread.
There are a couple of people in poughkeepsie over there having issues with WRGB 6.
Some have reliable signals now.
Have you looked at your TVFOOL report, to see what you can expect to receive?

Yeah, I've been following and have posted on the Albany thread and am pretty familiar with what the signal strength is like in my area. However, my remaining question is more antenna specific. Basically, what are the best Antennas for Channel 6 and will any of them fit into a 12'x10' space? Also, it would be nice to know what kind of gain I am getting on my current antenna, since I'd hate to spend $100+ on a monster antenna that really didn't do any better on Channel 6.

IIdeally, I want an antenna that can pull in 6-13,

You won't find such a beast, because the VHF-LO (2-6) and VHF-HI (7-13) bands are distinct, and widely separated. Channels 6 and 7 are about three times further apart than 2 and 6 are. See for example the table at

http://www.arrl.org/tis/info/catv-ch.html

You won't find such a beast, because the VHF-LO (2-6) and VHF-HI (7-13) bands are distinct, and widely separated. Channels 6 and 7 are about three times further apart than 2 and 6 are.

The new CM Advantage combos might fit the bill, but I have yet to see one or hear of anyone who has one:

http://www.solidsignal.com/pview.asp?p=CM-2018

They are wide enough to support FM, or so they have told me, but I have no verification of this.

You won't find such a beast, because the VHF-LO (2-6) and VHF-HI (7-13) bands are distinct, and widely separated. Channels 6 and 7 are about three times further apart than 2 and 6 are. See for example the table at

http://www.arrl.org/tis/info/catv-ch.html

Of course you're right that VHF-Lo and Hi are widely separated, but people still design and sell VHF antennas intended to pick up both bands (2-13). You'd think that since post-transition, channels 2-5 are virtually non-existent, someone would modify one of these designs for 6-13. Such an antenna should be ~30% smaller and would likely provide better gain on channel 6. Of course given that there are only something like 40 stations broadcasting on Channel 6, maybe it's not worth the effort?

On a related note, if I tried cutting the longest elements on my existing antenna, which appear to be about 107" (close to the Ideal Dipole for Channel 2) down to 71" (Ideal Dipole for Channel 6) would I expect to see an improvement in gain for channel 6? Would I lose gain on the higher channels or would they be unaffected?

Of course you're right that VHF-Lo and Hi are widely separated, but people still design and sell VHF antennas intended to pick up both bands (2-13). You'd think that since post-transition, channels 2-5 are virtually non-existent, someone would modify one of these designs for 6-13.

For the record there are only 9 stations on Ch 6 and 17 on Ch 5. Heck I have TWO channel 5s in my state. So if one were to modify for 6 they might as well modify for 5.

Excerpted from Falcon_77's spreadsheet (posted on rabbitears.info). The last line was added to highlight the relevant post-transition VHF low allocations.

Full Power Stations by Channel

Analog DTV Total *DTV
Pre-Trans*Pre-Trans*Pre-Trans*Post Trans*Avg*Avg
ch # # # # CH ERP Band ERP # of ch st/channel # of stations
2 59 9 68 6 11.0
3 62 4 66 7 19.3
4 63 6 69 2 54.6
5 56 9 65 16 33.1
6 62 1 63 9 12.3 23.8 5 8 40
...............^ # of DTV stations per channel


Based on those numbers, it would be pretty pointless for a manufacturer to make the suggested modification.

The new CM Advantage combos might fit the bill, but I have yet to see one or hear of anyone who has one:

http://www.solidsignal.com/pview.asp?p=CM-2018

They are wide enough to support FM, or so they have told me, but I have no verification of this.

It's odd. Channel Master calls the 2018 a U/V/FM antenna, but then doesn't rate the low band gain.
http://www.channelmaster.com/support_attachment/Antenna%20Selection%20Guide29.pdf

The longest element should barely work on channel 6 and FM, but not so much on 2-5.

OK, so the 40 station number I remembered was for the entire VHF-Lo band, not just channel 6. So, it might be a stretch to tailor an antenna specifically for the Ch 6 market. However, between channels 5 and 6 there are a total of ~36 million viewers, which is a larger market than all of Canada. Such an antenna would still be 25% smaller than a corresponding 2-13 antenna.

Yeah, I've been following and have posted on the Albany thread and am pretty familiar with what the signal strength is like in my area. However, my remaining question is more antenna specific. Basically, what are the best Antennas for Channel 6 and will any of them fit into a 12'x10' space? Also, it would be nice to know what kind of gain I am getting on my current antenna, since I'd hate to spend $100+ on a monster antenna that really didn't do any better on Channel 6.

Antennacraft Y5-2-6. 112" X 80" 4.9 db gain. $29.99 plus shipping. Use a HLSJ to add it to your other antennas.

http://www.solidsignal.com/pview.asp?p=Y5-2-6
http://www.solidsignal.com/pview.asp?p=HLSJ

Of course you're right that VHF-Lo and Hi are widely separated, but people still design and sell VHF antennas intended to pick up both bands (2-13). You'd think that since post-transition, channels 2-5 are virtually non-existent, someone would modify one of these designs for 6-13.

Dual-band VHF antennas typically rely on the 3:1 relationship between the two bands; e.g. a dipole or dipole array which works for 60Mhz will also work at 180Mhz. You can't use that trick to get part of the low band and all of the high band.

You could build specific market antennas for some markets -- e.g. an antenna for Channel 6 and Channel 12 for Philadelphia, but there probably isn't much of a market for them.

Blonder Tongue makes them. Quite pricey though...

Blonder Tongue makes them. Quite pricey though...

You weren't kidding about "pricey". I wonder if any ham or commercial antenna vendors out there will work with you to build a custom antenna (i.e. a Ch 6 antenna) at a reasonable cost. Force 12 and antenex (Laird) immediately come to mind, I'm sure there are others. Might be worth a call to find out. Just a suggestion.

Cheers.

From the www.sutrotower.com website .... for those hoping to see improved digital coverage in the Bay Area.


Two out of the three masts have been finished and the crew is working on the third mast now.

If you're interested in seeing the progress on the Sutro Tower project, check out the photos on my web site:
http://www.larrykenney.com/sutrotwr.html

Larry
SF

Two out of the three masts have been finished and the crew is working on the third mast now.

If you're interested in seeing the progress on the Sutro Tower project, check out the photos on my web site:
http://www.larrykenney.com/sutrotwr.html

Larry
SF

Very nice pictures! Seeing the workers on the tower highlights the scale (i.e. how big it is). I imagine they are doing work with active transmitters nearby. If so, that's a lot of RF radiation up there. I wonder how that fits into the non-ionizing radiation exposure limits published in FCC OET 65. Leaving aside working at that height, definitely not something I'd want to do. :D

BTW do you know if the workers often find themselves above the fog layer? Years ago the a prof of mine in the San Jose State meteorology department had instrumented the tower as part of a research project. As I recall, the temperature difference could be quite remarkable from base (cool) to top (warm) when the marine layer was strong.

Cheers

I live in Central Jersey and put up a Winegard YA-1713. I have it pointed a NYC at 90deg Mag and it picks up WPVI ABC Ch 6 Philadelphia at 230 deg Mag almost as strong as WABC Ch 7 NYC. NYC is 34 miles away, Philly is 54 miles. My Winegard HD-9022 pointed at NYC picks up most of the Philly UHF as well.

My point is, Winegard YA-1713's ARE VHF 6-13 antennas.

OZ

I live in Central Jersey and put up a Winegard YA-1713. I have it pointed a NYC at 90deg Mag and it picks up WPVI ABC Ch 6 Philadelphia at 230 deg Mag almost as strong as WABC Ch 7 NYC. NYC is 34 miles away, Philly is 54 miles. My Winegard HD-9022 pointed at NYC picks up most of the Philly UHF as well.

My point is, Winegard YA-1713's ARE VHF 6-13 antennas.

OZ

Well, my new YA-1713 should be here on Tuesday, so I hope you are right! I'm a little skeptical that it will outperform my existing VHF antenna on Channel 6, but it should do better on the higher frequencies. If it does do better on 6 that would be great, as I can then aim it at Albany to get 6,7, and 12 and point my existing Antenna at NYC, where I already know I can get 11 and 13. Not sure why I haven't been able to get WABC. I kind of hope my antenna has a notch at 7. If not it's probably due to interference between WXXA-7 and WABC-7, which might mean I won't be able to get either.

It's probably due to interference between WXXA-7 and WABC-7, which might mean I won't be able to get either.

Consider stagger stacking to get either channel 7. www.anarc.org/wtfda/stagger.pdf

This may not be the right thread, so if it isn't please let me know of a better one. Anyway, I borrowed a spectrum analyzer from work and scanned the TV frequency spectrum in Colorado Springs. Pictures and text are at this link:

http://www.avsforum.com/avs-vb/showthread.php?t=141193&pp=30&page=209

Thought the group might be interested to see an example of what is really being received at the physical (RF) layer. :D
Cheers.

Very nice pictures! Seeing the workers on the tower highlights the scale (i.e. how big it is). I imagine they are doing work with active transmitters nearby. If so, that's a lot of RF radiation up there. I wonder how that fits into the non-ionizing radiation exposure limits published in FCC OET 65. Leaving aside working at that height, definitely not something I'd want to do. :D

BTW do you know if the workers often find themselves above the fog layer? Years ago the a prof of mine in the San Jose State meteorology department had instrumented the tower as part of a research project. As I recall, the temperature difference could be quite remarkable from base (cool) to top (warm) when the marine layer was strong.

Cheers

The stations are now having to switch to the auxiliary antennas during the day when the crew is working on the Northeast mast since they're closer to the temporary UHF antennas that are normally used. When they were working on the West mast, they were far enough away that they didn't have to switch. So they are watching levels up there!

As for the fog layer... I don't know.

Glad you enjoyed the pics.

Larry
SF

You weren't kidding about "pricey". I wonder if any ham or commercial antenna vendors out there will work with you to build a custom antenna (i.e. a Ch 6 antenna) at a reasonable cost. Force 12 and antenex (Laird) immediately come to mind, I'm sure there are others. Might be worth a call to find out. Just a suggestion.

Cheers.

There are several cut to channel/freq yagis made..some more expensive than others (Google "cut to frequency yagi" or "cut to channel yagi" and you'll find them)....Anything made for 6 and up (LPDA type) would also cover the FM band as well as aircraft (though aircraft are vertical and not horizontal like TV/FM usually is)..Using a 60Mhz antenna on 180Mhz wont work unless you are talking simple dipole...a yagi's pattern is distorted bigtime when used on the 3rd harmonic..the elements are not spaced properly (0.25 wavelength spacing is a sweet spot..but 3rd harmonic has them 3 times distant..thus blowing any decent pattern)

put up a Winegard YA-1713. I have it pointed a NYC at 90deg Mag and it picks up WPVI ABC Ch 6 Philadelphia
Channel 6 in Philly isnt really a good example to test out a vhf-low antenna. Theyve quadrupled their power. I can get it most of the time with a reflectorless SBGH from 61 miles away, that technically has high negative net gain on channel 6. So while the antenna may work for channel 6 in Philly, it may be miserable for channel 6 elsewhere.
Even with that power increase, that station still has issues covering its area that analog did fine.

Well, I got my new YA-1713 last night and so far it's a bust...

In preliminary testing, I couldn't get anything from NYC or Albany. Of course atmospherics or other factors may have been working against me, so I need to do more tests before I completely throw in the towel. Last night, my old Antenna was pulling in WRGB(6) pretty well, but got nothing for WXXA(7) and only the smallest blip for WNYT(12), so perhaps there wasn't much signal around in the 7-13 range. I didn't get a chance to point my old antenna toward NYC, where in the past WPIX(11) and WNET(13) have been relatively strong, so perhaps those signals were down last night as well.

Anyway, it seems pretty clear that the YA-1713 is less powerful than my old Taco antenna even in the 7-13 range. This suggests that the only consumer-grade alternatives that are likely to outperform the Taco on VHF are the behemoth combos like the CM3671B or the Winegard 8200U, both of which are >$100 and neither of which will fit in my attic! Even these may not do much better as they have only 2-3db more gain than the YA-1713.

My last hope is to scavenge some elements from an old Channel-cut FM antenna that I have lying around, cut them down to size, and extend the boom of the YA-1713. According to hdtvprimer, this could get me another 3-4 db or so. We'll see.

Well, I got my new YA-1713 last night and so far it's a bust...


Sorry to hear that. If you really wanted ch 6, the antennna should be OUTSIDE. I didn't realize you were going for an attic mount.

Here's mine - pointed at NYC picking up Phily CH 6 54 miles the other direction:



OZ

Sorry to hear that. If you really wanted ch 6, the antennna should be OUTSIDE.It will more than likely need to be outside for 7-13 as well. 65-70 miles is about the limit for reliable reception given the low digital power levels you are dealing with.

SemiChemE, did you try just one tuner with no splits or pre-amp?

If you really wanted ch 6, the antennna should be OUTSIDE.



He said that 6 is already working in the attic.

Maybe you guys can help me.

I've been in my house for 2 years and only recently decided to use the antenna mounted on the roof for ATSC in Media Center. I recently removed the old 300-ohm twin lead and installed quad shield RG-6 coax with compression F connectors and a balun at the antenna. It goes into a Pinnacle 800e USB ATSC tuner. I am looking to move up to a dual tuner (Aver Duet) but I want to address some reception issues first.

Here is my TV Fool survey:
http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3d8ecd4ed4d356de

My antenna looks equivalent to this: http://www.solidsignal.com/pview.asp?mc=03&p=ANC3016&d=Channel-Master-CM-3016-Suburban-Advantage-TV-Antenna-%28CM3016%29&c=TV%20Antennas&sku=020572030168

It is about 15' off the ground and the pole does not go into the ground.

I need to buy a compass but as far as I can tell by eye, my antenna is aimed roughly at the cluster of towers at 41° mag. I get all of the channels in this direction, except 50.1. I also get 5.1 and 2.1 @ 28° and 46.1 @ 53°. 28.1 @ 83° is marginal as is 38.1 @ 28°.

What I'd like is to fix the intermittent reception on 28.1 and 38.1 while not losing the Boston channels, 2.1, 5.1. And 69.1 (RF 17) @ 258° would also be desired, but I don't see how.

The real problem is 28.1 is off at 83°. And my antenna I think has about a 30° beam width, which is not wide enough to cover the 42° span between the channels I get strongly @ 41° and 28.1 @ 83°. Not to mention, turning the antenna might cause me to lose the 50 mile Boston stations @ 28°.

What are my options? I can't really go any higher due to the fact that my house is a ranch. Should I try to split the difference by aiming the antenna to around ~62°? Or should I go for something like this http://www.solidsignal.com/pview.asp?p=CM-2018
which promises a 45° beam width and 15 mile greater reception distance? Should I go with an amplifier to pull in off-axis stations?

Finally, I have a coax connector installation question. I had a heck of a time putting the connectors on. The inner foil kept getting pushed down when I tried to put the connector on and eventually I gave up at trying to get it perfect. The connector inside has partial foil all the way to the end of the dielectric and the one at the antenna is crushed all the way to the base of the F connector. After experimenting with a known good cable on the roof and laptop, I don't believe this is causing any problems at the frequencies involved. Can someone confirm or deny this?

Sorry to hear that. If you really wanted ch 6, the antennna should be OUTSIDE. I didn't realize you were going for an attic mount.

Here's mine - pointed at NYC picking up Phily CH 6 54 miles the other direction:



OZ

Yeah, I had planned to move my antennas outside, but when I got them up on the roof my wife complained and made me take them down. At this point, if I can't get something that works in the Attic, I'll probably either just break down and pay for cable or do without.

It will more than likely need to be outside for 7-13 as well. 65-70 miles is about the limit for reliable reception given the low digital power levels you are dealing with.

SemiChemE, did you try just one tuner with no splits or pre-amp?

So far, I've tried two configurations. First, with the YA-1713 mounted on it's own mast (actually a 6-ft step ladder) and connected with a 6-ft cable directly to the tuner (KWorld-UB435-Q). Second, with the YA-1713 mounted on the same mast as the Taco antenna and connected through a CM7777 pre-amp to a Venturer Set-top box. BTW, the Venturer box appears to be a re-branded version of the Winegard set-top box.

When I get a little more time, I'll do some more thorough testing, including recording the signal level from both Albany and NYC with the old antenna and then removing the old antenna and replacing it with the YA-1713 to see how it compares.

He said that 6 is already working in the attic.

Well, sort of working... I get a solid watchable signal from WRGB(6) about 30% of the time (usually between 9pm and dawn). Unfortunately, WNYT (12) tends to be a bit weaker and WXXA(7) is rarely watchable. I expect this to improve significantly as the nights get longer and the leaves start to fall from the trees. If the FCC ever approves WRGB's and WNYT's applications to boost power, I should be in pretty good shape. The frustrating thing is that the Albany UHF stations come in great on my C4 antenna, but most of the major networks are on VHF.

I recently removed the old 300-ohm twin lead and installed quad shield RG-6 coax with compression F connectors and a balun at the antenna...... Should I go with an amplifier to pull in off-axis stations?
Replacing the 300-twin lead with RG6 is a good start because the coax is less affected by changes in the weather. But, coax has a higher loss than the twin lead: about 6 dB per 100 ft for UHF. How long is your coax downlead?

A preamp at the antenna will makeup for the signal loss in the downlead, but it is not a good solution for off axis-aim of the antenna because off-axis aim increases the multipath reflection errors for the desired station which makes it harder for your tuner to lock on to the signal, especially when the signal is weak to start with.
What I'd like is to fix the intermittent reception on 28.1 and 38.1 while not losing the Boston channels, 2.1, 5.1. And 69.1 (RF 17) @ 258° would also be desired, but I don't see how.
How would you feel about using a rotator to optimize antenna aim? If you don't want a rotator and still want 69.1 you could have a 2nd antenna aimed at it and use a A/B switch.

Replacing the 300-twin lead with RG6 is a good start because the coax is less affected by changes in the weather. But, coax has a higher loss than the twin lead: about 6 dB per 100 ft for UHF. How long is your coax downlead?

Hmm, I didn't actually realize it had greater loss. I assume there was a net gain by replacing the old twin lead, though. Or I'd like to assume so.

The length is probably 60 to 70 feet. I could shorten it by maybe 10 feet. I left some extra in the garage.


A preamp at the antenna will makeup for the signal loss in the downlead, but it is not a good solution for off axis-aim of the antenna because off-axis aim increases the multipath reflection errors for the desired station which makes it harder for your tuner to lock on to the signal, especially when the signal is weak to start with.

How would you feel about using a rotator to optimize antenna aim? If you don't want a rotator and still want 69.1 you could have a 2nd antenna aimed at it and use a A/B switch.

Yeah that makes sense about the amp.

Unfortunately I think a rotator is not in the cards as I can't really justify the expense, inconvenience - plus I'm using media center for my DVR so I don't see that working out.

What about adding the second antenna but using a signal combiner? 69.1 is only 20 miles and I got partial reception on the roof with a simple telescoping antenna that came with the USB ATSC tuner. Does that mean anything? It's about 180d off the 28.1 channel. Is there any way to get an antenna that has enough gain from the rear to pick up this station?

And what do you think about my current antenna in the context of my goals, as well as the replacement I linked to?

He said that 6 is already working in the attic.

Actually, I don't know if he is referring to the YA-1713 or not. First he says:

"my old Antenna was pulling in WRGB(6) pretty well"

Then he says (about ch 6, no mention of the YA-1713):

"Well, sort of working... I get a solid watchable signal from WRGB(6) about 30% of the time (usually between 9pm and dawn)"

Whatever he means, what I said is relevant, if he wants a good signal (from either the old or new antenna), it should be outside.

That's my last 2 cents.

OZ

I need to buy a compass but as far as I can tell by eye, my antenna is aimed roughly at the cluster of towers at 41° mag.

You might try using google earth instead of a compass. You should be able to search for the towers in google earth and then draw a line from them, directly to the location of your antenna. Then it's just a matter of locating a visible reference or two on that line and pointing there. I found this much easier then using a hand held compass and translating where the compass was pointed to where the antenna points. Tvfool has links to the files that contain the transmitter placemarks and coverage.

http://www.tvfool.com/index.php?option=com_content&task=view&id=15&Itemid=1

What about adding the second antenna but using a signal combiner? 69.1 is only 20 miles and I got partial reception on the roof with a simple telescoping antenna that came with the USB ATSC tuner. Does that mean anything? It's about 180d off the 28.1 channel. Is there any way to get an antenna that has enough gain from the rear to pick up this station?
First try picking up 69.1 off the back of your present antenna or the CM antenna like it. If that doesn't work try a combiner for two antennas, one of which is for UHF 17 aimed at 69.1. When you use a combiner, the two signals from the same station might interfere with each other. If so, go with the A/B switch or add a filter such as a jointenna for channel 17 which will pass 17 but block the rest of the channels on one port and block 17 and pass the rest on the other port to avoid the interaction. The third port is the combination of the other two.
What are my options? I can't really go any higher due to the fact that my house is a ranch. Should I try to split the difference by aiming the antenna to around ~62°? Or should I go for something like this http://www.solidsignal.com/pview.asp?p=CM-2018
which promises a 45° beam width and 15 mile greater reception distance? Should I go with an amplifier to pull in off-axis stations?
I'm skeptical about a manufacturer claiming that an antenna has wider beamwidth and geater gain because the two are mutually exclusive. An antenna must have narrower beamwidth to have greater gain. Perhaps they were quoting the VHF-hi section beamwidth as the beamwidth for the antenna even though the UHF beamwidth might be different.

The 2018 is suitable for your situation, but sometimes, because of so many factors, you just have to try it.

When I was a kid my father to me to my first stock car race at Kingston. We had relatives in Weekapaug (they had more money than we had).

You might try using google earth instead of a compass.

I actually did that using the FCC maps site and that's how I can tell it's pointed in roughly the right direction. But in my area, it is very hard to locate landmarks because of the dense pine trees overhead. I bought a compass today at Expensive Mountain Supplies and will give it a try.

First try picking up 69.1 off the back of your present antenna or the CM antenna like it.

That doesn't really work currently. It worked better with the cheap telescoping metal antenna that came with the USB tuner (on the roof, mind you). But perhaps if I aim my antenna to split the difference between 28.1 and the rest, the rear will be closer to pointing at 69.1.

If that doesn't work try a combiner for two antennas, one of which is for UHF 17 aimed at 69.1.

That sounds awesome. I wonder if I could get away with a really simple antenna just aimed correctly since all I need is 69.1 in that direction. I'll look those guys up and see what they have, if I decided to go that route.

EDIT: I looked into the jointenna product. It says there is significant attenuation for channels directly adjacent to the blocked channel. 69.1 is RF 17. I have a 50 mile Boston PBS at RF 19 and the Boston ABC I don't want to lose at RF 20 (though I have RI PBS and RI ABC available). 21 is a RI PBS and 22 is the 28.1 that I am trying to receive stronger. Are any of these in danger of being attenuated with the jointenna?

I'm skeptical about a manufacturer claiming that an antenna has wider beamwidth and geater gain because the two are mutually exclusive. An antenna must have narrower beamwidth to have greater gain. Perhaps they were quoting the VHF-hi section beamwidth as the beamwidth for the antenna even though the UHF beamwidth might be different.

Well I think it's a larger piece (EDIT: actually it isn't), and since it's "HD" it goes from 7-69 rather than 2-69, so perhaps losing the lower VHF band will increase the gain on the rest of the channels? I don't know anything about antenna design though (despite being a EE). I also just realized that perhaps the HD designation means the range specification is given in terms of the digital transition. All I really need is the gain plots to know for sure.


The 2018 is suitable for your situation, but sometimes, because of so many factors, you just have to try it.

Yeah it's cheap enough. Is there any reason, other than lightning grounding, to put the pole all the way into the ground?

Also I thought more about the foil shielding question on the F connectors. I think any loss I am seeing is due to the loss of the cable itself, compared to the 8 footer I was using on the roof. So I guess re-terminating wouldn't buy me anything except high blood pressure.

When I was a kid my father to me to my first stock car race at Kingston. We had relatives in Weekapaug (they had more money than we had).

Kingston RI? I guess that's technically the South Kingstown area. I actually moved out this way in 2004. Born and raised in the greater Hartford, CT area prior to that.

Are any of these in danger of being attenuated with the jointenna?
Sometimes it works when adjacent channels are close, sometimes it doesn't. Each filter is designed for a section of the UHF band and must me tuned by a tech for the channel of interest before it is shipped to you. They don't always do a good job. Tinlee in Canada makes better filters, but they are more expensive----like about $100.
All I really need is the gain plots to know for sure.
So do I, but I couldn't find them.
Is there any reason, other than lightning grounding, to put the pole all the way into the ground?
Not that I know of, as long as your mast is supported securely enough to survive an ice storm and your grounding system meets the new NEC regulations. You wouldn't want to give your insurance company a reason to deny a claim if there was a problem.

I forgot to mention there is also RF 13 and RF 12 that I can't lose. They are a little farther from RF 17 than the 19 to 22. Perhaps a unit tuned at 15 or 16 might work better since RF 12 and 13 should be fairly strong for me.

Tinlee in Canada makes better filters, but they are more expensive----like about $100.


I would absolutely pay a premium for a better tuned filter, especially if it had a more narrow band cut range. I'll look them up.

Here's the Tin Lee link for you:
http://www.tinlee.com/index.php
http://www.tinlee.com/Matv_filters.php?active=3
http://www.tinlee.com/catv_filters.php?active=1

I understand that their engineers are easy to talk to if you give them a call.
I forgot to mention there is also RF 13 and RF 12 that I can't lose. They are a little farther from RF 17 than the 19 to 22. Perhaps a unit tuned at 15 or 16 might work better since RF 12 and 13 should be fairly strong for me.
RF 12 and 13 are in the VHF-hi (7-13) band. UHF starts at CH 14. There is a big frequency gap between 13 and 14 for OTA reception.
http://www.tinlee.com/FreqChart.php?active=

Here's the Tin Lee link for you:

I understand that their engineers are easy to talk to if you give them a call.

RF 12 and 13 are in the VHF-hi (7-13) band. UHF starts at CH 14. There is a big frequency gap between 13 and 14.

Thanks I already found their website. I'll probably give them a call.

I just realized 12 and 13 are not in any danger. And that huge gap would allow me to get a filter that blocks 17 adequately from the primary antenna but doesn't hurt the Boston RF 19 and 20. 21 should be fairly strong but 22 is the off axis one that I am having problems with now. This could be dicey. I could just write off ION (RF 17) and focus on getting 28.1 while maintaining the Boston stations. I guess that is what I have to decide - can I lose a PBS and ABC that I already have RI versions of to gain an ION? The Boston ABC uses 1080i according to the silicon dust website, while the RI ABC uses 720p. Figures. I probably don't need two PBSs.

EDIT: I'm writing an e-mail to Tinlee and I just realized something. I need the RF 17 band pass on the secondary antenna so it doesn't pick up reflections on the stations the primary antenna receives. But I may not need an RF 17 cut on the primary antenna, because it doesn't really receive the channel anyway (due to being almost 180° off).

Also according to silicon dust, the 4 ION stations are either 480p or 480i...one of my driving points for this entire project was free HD so maybe I should just write off ION (RF 17).

Don't mind me, just thinking out loud.

Just found another good looking Channel Master antenna, the CM2020: http://www.solidsignal.com/pview.asp?mc=03&p=CM-2020&d=Channel-Master-CM-2020-Digital-Advantage-TV-Antenna-%28CM2020%29&c=TV%20Antennas&sku=020572030168

This one promises an even 60mi VHF AND UHF, with the same can-it-be 45° beam width.

It goes into a Pinnacle 800e USB ATSC tuner. I am looking to move up to a dual tuner (Aver Duet) but I want to address some reception issues first.
I forgot to ask you: Are you able to add another channel from a different direction after your initial scan without erasing the initial scan channels?

I actually did that using the FCC maps site and that's how I can tell it's pointed in roughly the right direction. But in my area, it is very hard to locate landmarks because of the dense pine trees overhead. I bought a compass today at Expensive Mountain Supplies and will give it a try.

At TVfool, you can plot station azimuths on a Google satellite map (use "Start maps" option). If you can zoom in far enough, you can see pretty accurately how to aim based on landmarks.

I forgot to ask you: Are you able to add another channel from a different direction after your initial scan without erasing the initial scan channels?

If you're not familiar with media center here's how Vista Media Center does it: there is an initial channel scan upon first initialization of a tuner. You are then advised to visit the signal strength test screen where it will loop through all available channels (available meaning they are known to the electronic program guide by your zipcode) and display signal strength in bars, 1 to 6. Generally I've found that anything 3 bars and below is probably marginal.

Inside the screen, you can check or uncheck individual channels which removes them from the EPG and stops scanning them on the loop. I can go back at any time and run this loop and uncheck or check different channels. I can also manually add a channel, which is the only way to add sub-channels in Vista Media Center. I think this is what you were asking but all I'd do based on what I mentioned above is go back into that scan screen and either check off channels I think I might get now, or just check them all off and let it cycle through everything a couple times before I go back and remove the dead ones.

Windows 7 Media Center handles this WAAAAY better (including displaying the ATSC Vchan and subchannel in the correct format), as I am running Win 7 RC1 on a laptop and first tried the tuner on it, where it did a great job of finding the stations AND subchannels.

Thanks.
My knowledge of Media Center is very slight.

Do your tuners give bit errors as well as signal strength, and if so in what form?

I hope you will let us know how your project worked out.

At TVfool, you can plot station azimuths on a Google satellite map (use "Start maps" option). If you can zoom in far enough, you can see pretty accurately how to aim based on landmarks.

I already had satellite map data. I'm saying in new england the tree density is just too high to locate anything meaningful on a map like that. Not to mention I can't really even see the street that the transmission path crosses.

Anyway, I just measured the antenna magnetic bearing. It is 47 degrees. Most of my channels are at 41d. 3 are at 28d (Boston, 50 miles). And 28.1, that I am working on, is at 83d (30 miles). Maybe I'll try moving the antenna 10-15 degrees to the right and hope I can gain 28.1 without losing the Boston stations at 28 degrees.

Or I'll get the CM2020 and hopefully get it all. And if I am REALLY super lucky, it will have a large enough gain section at the tail to receive 69.1 @ 257d, only 19 miles.

Found some info.

http://www.starkelectronic.com/cm2018.pdf

http://www.starkelectronic.com/cmant.htm

Search the page for 2018 and 2020. There are some gain and beam width specs. I am going to make a rudimentary plot in Excel and see if anything jumps out at me. The beam width is given in terms of -3dB and F/B is the front to back ratio. It doesn't tell me the shape but perhaps it's the same width as the front, just less gain by the F/B column?

http://www.starkelectronic.com/cm2018s.jpg

http://www.starkelectronic.com/cm2020s.jpg

If RF 22 is off axis from the others, which do I want? 2018 has a wider beam but 2020 has higher gain. Since RF 22 @ 83d is 30 miles and the Boston channels are at 28d, perhaps 2018 would actually be a better choice. They both lose about 15dB on the back. I wonder if that would leave me with enough on that RF 17 channel behind me.

Here is the composite plot of both antennas' beam width and gain. I think that the 2018 may be the superior choice because of its wider beam in the RF channels of interest. The strong ones I get at 41d are likely not an issue. If I want to get RF 22 @ 83d without losing RF 19 and 20 @ 28d, it seems the width of the 2018 would overrule the 2020's gain here. Thoughts?

http://kevinallenmoore.com/photo/d/81830-1/CM_gain.gif

Ok, last edit before bed.
Look at my TV fool survey again.
http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3d8ecd4ed4d356de

There is both an ION (RF 32) and a CW (RF 41) @ 29d (more 50 mile Boston stations). Perhaps an alternate plan is use the narrower beam 2020 and point it between 28 and 41 and get everything. And bonus, Boston's ION is 720p according to the Silicon Dust website. Interesting.

FYI: For those of you contemplating using YA-1713 (Ch7-13) antenna to receive Ch6.
According to 4nec2 simulation runs, on Ch6 Raw Gain=2.5 dBi, F/B=0.4 dB and SWR=300
(using YA-1713 measurements from a year ago) or SWR=150 (per Ken Nist's file posted on
www.hdtvprimer.com several years ago).
The earlier YA-1713's had significantly different element spacings and diameters.

Below Ch6, the Gain remains above 2.0, but the SWR keeps climbing.....into the thousands....

So, yes it has some positive Gain, but doesn't suppress multipath coming from the rear
and has excessive SWR that could result in a null on Ch6 for certain cable lengths
(so add extra cable length until it goes away), but also causes lots of reflections up and down
a long coax, which looks like short delay multipath and can degrade Ch6 receptions (YMMV....)
Direct connect to a Preamp should minimize this latter problem if overload isn't an issue....

I'm skeptical about a manufacturer claiming that an antenna has wider beamwidth and geater gain because the two are mutually exclusive. An antenna must have narrower beamwidth to have greater gain. Perhaps they were quoting the VHF-hi section beamwidth as the beamwidth for the antenna even though the UHF beamwidth might be different.

The 2018 is suitable for your situation, but sometimes, because of so many factors, you just have to try it.

CM-2018 (et. al.) detailed specs are in the fol. catalog:
http://www.channelmasterintl.com/documentation/catalogs/Channel%20Master%20Catalog_200903a_20090417.pdf
Note that 45-deg beamwidth applies to highest UHF channels, narrows down to 35-deg for mid-UHF,
widens out to 54-deg for low-UHF and widens even further (as expected) for Hi-VHF....

But are conveniently missing from where they should be (hidden actually) on the C-M website:
http://www.channelmaster.com/product-overview.php?proID=32&catID=33
http://www.channelmaster.com/support_attachment/Antenna%20Selection%20Guide29.pdf

But are conveniently missing from the C-M website:


I found this:

http://www.channelmasterstore.com/ProductDetails.asp?ProductCode=CM-2020&Show=TechSpecs

Does anyone have any input on how the CM-2020 compares with the Winegard 7697 or 7698? Cost is not the concern...these are all cheap. I just want the superior product. Looking for gain and BW specs or a chart for the Winegard antennas. I'll post if I find anything, comparing them to the CM's.

EDIT. Done. Wow, the Winegard products appear to be noticeably superior to the Channel Master pair. With that much gain, am I at risk for tuner overloading for my 19 mile stations?

http://kevinallenmoore.com/photo/d/81838-1/CM-WG_gain.gif

EDIT: I looked into the jointenna product. It says there is significant attenuation for channels directly adjacent to the blocked channel. 69.1 is RF 17. I have a 50 mile Boston PBS at RF 19 and the Boston ABC I don't want to lose at RF 20 (though I have RI PBS and RI ABC available). 21 is a RI PBS and 22 is the 28.1 that I am trying to receive stronger. Are any of these in danger of being attenuated with the jointenna?

I'm using a jointenna for channel 19 but still wanted 17. I tested the drop in signal level for 17 and found it to be roughly 9dB. I had enough signal so everything worked fine.

I think I've devised a way to just use an antenna with good gain pointed in a narrow 13 degree beam to capture all the RI stations from 41d and hopefully all the Boston stations from 28-29d. Going by TV Fool, ION (RF 32) is 25.1NM and -65.7 for power, and this is the weakest station I would need to receive. According to the Feds, I am just on the edge of the map for this station, though I don't know what antenna height they assume.

I think I have the antenna choice narrowed down to either of the Winegards I posted. The 11 foot 7697P or 14 foot 7698P. The 7678P puts in its best showing over 7697P at, you guessed it, RF 32. It has 1.6dB over the 7697P at 32. Is that enough, considering the weakness of RF 32, to go with the 7698P or will I be totally fine with the 7697P?

What I am getting at is I think a 14 foot antenna on my roof might look pretty ridiculous but an 11 foot might be on the edge of kind of OK...but it would be a shame if the 7698P made the difference.

Winegard Antenna Specs:
http://www.winegarddirect.com/
http://www.winegard.com/kbase/upload/WC-939%20OTA%20Product%20Cat.pdf
http://www.winegard.com/offair/antenna_list.php

AntennaCraft Antenna Specs:
http://www.antennacraft.net/

I think I've devised a way to just use an antenna with good gain pointed in a narrow 13 degree beam to capture all the RI stations from 41d and hopefully all the Boston stations from 28-29d. Going by TV Fool, ION (RF 32) is 25.1NM and -65.7 for power, and this is the weakest station I would need to receive. According to the Feds, I am just on the edge of the map for this station, though I don't know what antenna height they assume.

I think I have the antenna choice narrowed down to either of the Winegards I posted. The 11 foot 7697P or 14 foot 7698P. The 7678P puts in its best showing over 7697P at, you guessed it, RF 32. It has 1.6dB over the 7697P at 32. Is that enough, considering the weakness of RF 32, to go with the 7698P or will I be totally fine with the 7697P?

What I am getting at is I think a 14 foot antenna on my roof might look pretty ridiculous but an 11 foot might be on the edge of kind of OK...but it would be a shame if the 7698P made the difference.

I went from an 11 foot radio shack antenna to a 14 foot winegard and it doesn't look much different from the ground. My signal strength increased almost 5 fold with the biggest gains on channel 6. For low VHF bigger is almost always better. Superior design is important also and winegard has that in spades.

True, but I've got something that looks like this:
http://pimages.solidsignal.com/CM3016_zoom.gif

I think I've decided on the 7697P, 11 foot, but I'm kinda hoping someone looks at my TV fool survey and can judge my potential reception from the towers at 28 to 41°, based on the antenna gain plots.

Speaking of which, where did they go?

Ah, permissions issue on my Gallery. Should be fixed now. You guys must have thought I was crazy. Well anyway, check out my gain and beamwidth plots.

I ordered the WG-7697P. It cost me 2 months of analog expanded cable, or $106. TV Fool has me mostly confident that I'll be able to receive my blue area stations without a pre-amp from 15 feet. And without a pre-amp, I won't need to worry about overloading the tuner with the 19 mile stations. I'll report back how it all goes. I already know to expect the antenna to arrive somewhat compromised from shipping/poor packaging. Hope I can manage the install by myself. If not I'll bribe some friends...

I expect about 24 total channels when I am done. Getting about 12 now, plus 2 marginal ones. I also expect a full 12 of those 24 to be HD. Currently I get about 7 in HD, plus the 2 marginal ones.

kevm14,

I think you'll get more stations than you expect. I replaced my old antenna with a stacked HD-9022 and a YA-1713. I went from 28 ch (maybe 16 usable) to 52 with about 40 usable, though you need to speak Spanish or Korean for 1/3 of them. I also have a WD 8275 preamp on now. Here's how bad my area is:


OZ

Speaking of which, where did they go?
Many of us are still here, but if we don't have anything useful to say, we are quiet. Also, we don't want to give any bad advice. If we do, the Moderator or other regulars will shoot us down!
Ah, permissions issue on my Gallery. Should be fixed now. You guys must have thought I was crazy. Well anyway, check out my gain and beamwidth plots.
Nice job on the plots. I enjoyed looking at your Gallery by going to the root URL.
I think I've decided on the 7697P, 11 foot, but I'm kinda hoping someone looks at my TV fool survey and can judge my potential reception from the towers at 28 to 41°, based on the antenna gain plots.
You showed us your tvfool results and told us what channels you were interested in, you told us about your reception equipment, we talked about the possible options for you, and the appropiate antenna types. The engineer in you has done a good job of analyzing the possibilities, now it is time for you to select an antenna and let the technician in you test it out. When you are up there it might be interesting to temporarily swing your new antenna toward 69.1 (if you decide on a 2nd antenna just for 69.1, it will be a lot smaller being just for UHF).

The reason why you must be the final person to make the decision is because there are still some unique unknown factors at your location that would be difficult to analyze. The main one has to do with the fact that with digital, signal quality is just as important as signal strength while with analog, signal strength was all-important.

The digital tuner has an error correction system (FEC) that will correct a limited number of errors in the digital stream. Once that limit is reached, you will start to see tiles, picture freeze, and dropout when you are at the "digital cliff." Signal quality is measured by BER (bit error rate/ratio). The factors that increase BER and reduce signal quality are:

1. Improper signal level: A weak signal will cause a poor signal-to-noise ratio; a signal that is too strong can overload a tuner or preamp. A nearby FM transmitter can also cause overload, which would require an FM trap.
2. Reflections from multipath problems, static or dynamic.
3. Impulse noise in the reception area (worse on VHF).

It IS possible to have a strong but poor quality signal.

Now you know why (in post 10278) I asked about your tuner/software being able to give BER, in addition to strength. It would be useful if it also gave SNR, which should be at least 15.5 to 16 dB to obtain lock on a digital signal. I use the signal quality bar on my Apex DT502 CECB to tell me about signal quality which helps me to optimize antenna aim after first going for max signal strength.
What adds confusion to good reception is that some tuners are more tolerant of a poor quality signal than others as AntAltMike can attest:
http://www.avsforum.com/avs-vb/showpost.php?p=15579378&postcount=16

Because my tuner is also my BER meter, the correlation is good.

Since I don't know your EE area of knowledge, I might be preaching to the choir. If so, sorry.

Wow that is a bad area. What is your antenna height?

Also I looked up those antennas. They are pretty high gain. How much do you think you lose by splitting? And do you have them pointed in the same direction? You have a lot of stuff at 90d but not everything.

You know what else I realized...you probably don't need a fancy band pass/cut combiner. You might even be able to use a splitter backwards. What do you use?

Many of us are still here, but if we don't have anything useful to say, we are quiet. Also, we don't want to give any bad advice. If we do, the Moderator or other regulars will shoot us down!


Actually that comment wasn't directed at a person. It was an expression of frustration because I loaded this thread this morning from work only to realize my plots weren't showing! They showed at home when I posted because I was signed into my Gallery as an admin but I forgot to turn on a setting that allows guests to view the original size of an image. I didn't mean to sound like I was whining or something.


Nice job on the plots. I enjoyed looking at your Gallery by going to the root URL.

Thanks and thanks.

The engineer in you has done a good job of analyzing the possibilities, now it is time for you to select an antenna and let the technician in you test it out. When you are up there it might be interesting to temporarily swing your new antenna toward 69.1.

I knew I was at that point and that is why I placed the order today. Good news, too - the antenna has shipped from Solid Signal and will arrive by wednesday!!

I know I get stuck in the research phase far too long but I have just been burned for what like seems over and over again for making decisions faster than I feel comfortable, only to lack the full comprehension of the situation. In many cases, I've found that if I was a little more patient I would have done a better job at whatever process or product is being discussed.


The reason why you must be the final person to make the decision is because there are still some unique unknown factors at your location that would be difficult to analyze.

I do have a few trees very close to the antenna but I am hoping that by pointing the antenna to ~32-35d instead of 47d I will miss the big white pine trunk. There's a smaller tree that I can get rid of myself. I just had 4 giant white pines removed from my front yard 2 weeks ago, by the way.


The digital tuner has an error correction system (FEC) that will correct a limited number of errors in the digital stream. Once that limit is reached, you will start to see dropout, tiles, and picture freeze. Signal quality is measured by BER (bit error rate). The factors that increase BER and reduce signal quality are:

I am using a USB tuner at the moment and will be upgrading to an internal PCIe card with a dual internal tuner when I build my HTPC. That's another reason why I am concerned. I guess if I had to add a preamp I will, especially if I end up missing one of the networks I don't have a duplicate of.

Generally, I think external consumer electronic set top tuners, as well as those built into newer TVs, are regarded as being more sensitive than the PC-based internal or external devices.

I have no way to determine signal strength (other than the 6 bars in Media Center), unless I find some software that I can download and use independently of media center just for setup purposes. No idea on FM.

And I'll check that thread out.

I know I get stuck in the research phase far too long but I have just been burned for what like seems over and over again for making decisions faster than I feel comfortable, only to lack the full comprehension of the situation. In many cases, I've found that if I was a little more patient I would have done a better job at whatever process or product is being discussed.
I know the feeling well. Been there, done that.

Your fmfool report for zip 02852:

http://i496.photobucket.com/albums/rr328/rabbit73_photos/Radar-FM02852.png

I never use FM but...that seems like a lot. Am I going to have a problem?

I never use FM but...that seems like a lot. Am I going to have a problem? Wish I had that problem:)

Is my "problem" enough to require an FM trap?

Also, I guess this is life in southern new england. I'm just lucky that my home's location works out so RI station transmitters and many Boston transmitters are within a 13° beam spread of each other. The WG 7697P comes tomorrow. The day of reckoning...or perhaps it's more of a weekend job.

Just took down a huge HD8200P and added an 2nd XG91 (all stations I want are now UHF). I now have a vertical stack with the two XG91s about 4' apart. They are combined on the mast and feed a Winegard AP-8275. I expected a BIG improvement over 1 XG91, but see only a very small improvement (a few % maybe). I used equal length 6' RG6 to the combiner (http://www.directdepot.net/product_i...ducts_id=22826) to the preamp. Maybe horz. stack is better but vert. was easy because I had a 4' mast to add. Shouldn't I see a bigger improvement??

Generally, I think external consumer electronic set top tuners, as well as those built into newer TVs, are regarded as being more sensitive than the PC-based internal or external devices.
Theyre getting better. I recently got a (open box at Newegg, $37) AVerTV Bravo Hybrid PCI-E which has a 6th generation tuner. Directly testing it on the same line, and at the exact same time as my Zenith DTT901 CECB, the PCI-E card drops out just a millisecond before the DTT901 does on a weak signal. :) And its about a millisecond slower to recover.

Theyre getting better. I recently got a AVerTV Bravo Hybrid PCI-E which has a 6th generation tuner. Directly testing it on the same line, and at the exact same time as my Zenith DTT901 CECB, the PCI-E card drops out just a millisecond before the DTT901 does on a weak signal. :) And its about a millisecond slower to recover.

I had picked out the Avermedia Duet since I want a dual tuner with internal splitter. Any thoughts on that one? It is fairly new as well. Newer than the other competing dual tuner on the market, the Hauppauge 2250 (which also does NTSC).

I never use FM but...that seems like a lot. Am I going to have a problem?You should be fine. With a 7-69 antenna, you are likely OK unless you are right on top of any strong FM station(s). (0-5 miles)

I've got a new Antennas Direct Clearstream 5 and am very pleased with how it works. I wanted something that would pick up the two VHF stations in this market without having to use a rotor. (A rotor and DVR don't work well together. :) ) The C5 was listed a multidirectional antenna, so I thought I'd try it. I planned to couple it up with the Antennas Direct SR-15 I have for UHF.

Well, much to my surprise, with the antenna pointed toward Mt. San Bruno at 178 degrees and peaked for KNTV channel 12, I not only get a good signal on 12, but KGO on channel 7 is coming in at 33 db SNR from Sutro Tower which is to the west at 267 degrees.

But that's not the end of the story. I'm also getting excellent signals on ALL of the UHF stations on Sutro Tower and Mt. San Bruno, plus decent signals from all of the stations transmitting from the hills above Fremont 35 miles to the southeast, including a low power 12.2 kw station. That's with just the C5 by itself... no SR-15.

The C5 is a weird looking antenna, but it seems to perform very well. Now I can use the SR-15 for something else.

Larry
SF

I've got a new Antennas Direct Clearstream 5 and am very pleased with how it works.

Can anybody else second this?
I thought early users of the C5 hated it and sent it back, there being no good substitute for a Yagi-style antenna for receiving high VHF...

So I installed my hdp-269 and it works great. Channel 19 comes in fine after the jointenna and a two way split. My antenna is on the eave of the house so the cable drops into the attic and through a ceiling, and then connects to the tuner in a closet, so its a short run. To test it before I got on the roof, I put it in-line at the end of the run before the jointenna. Everything works fine now so I'm tempted to leave it there as opposed to mounting it on the mast, outside exposed to the elements. Is there any reason not to if things work fine? Am I overlooking something due to inexperience?

Can anybody else second this?
I thought early users of the C5 hated it and sent it back, there being no good substitute for a Yagi-style antenna for receiving high VHF...If you live in an area with very low levels of multipath, and decent signal strength, the C-5 may work just fine. A real windy day is the real test for such a non- directional antenna.

Can anybody else second this?
I thought early users of the C5 hated it and sent it back, there being no good substitute for a Yagi-style antenna for receiving high VHF...

Nonsense. According to a little birdie, returns have been less than 2% and most of them were from people who didn't know what they were doing or self-selected the wrong antenna. About 1/4 of the returns were never even assembled.

Most posters here (on AVSforum) only come on when they have problems. You rarely hear the success stories. Station engineers who received samples of the C5 to try out have reported excellent results. One even reported good results with it on VHF-5 at about 25 miles, something that was unexpected.

If you live in an area with very low levels of multipath, and decent signal strength, the C-5 may work just fine. A real windy day is the real test for such a non- directional antenna.

At about 6 dbd on high-VHF, the C5's gain is almost exactly the same as the recommended antena gain that the FCC uses in calculating service coverage (OET-69 Planning Factors).

The C5 is basically a scaled-up C1. It exhibits similar beamwidth (70°) and F/B performance (around 10-12 dB based on testing). It is classified as "multi-directional". Gain-wise, it's roughly equivilent to a 5-element Yagi but with a broader beamwidth. However, it isn't 5 feet long which makes it an attractive option for a lot of people. Of course, if greater gain and/or directivity is needed, then a 10-element Yagi would be suggested.

I played with a C5 a couple of weeks ago using my 1454 hand-held spectrum analyzer. I was able to see the signals on the SA screen from VHF stations on 8 & 12 from over 70 miles away at a height of only 10' above ground (good atmospherics that day!). I am in the middle of two VHF-8 stations and could see both of them when the antenna was pointed at each. I was able to get a partial decode on them with my USB tuner, but I forgot to bring a power supply for my pre-amp with me so I wasn't able to try it with a pre-amp. Maybe some other time...

FWIW, the TVfool forcasts for those stations are pretty dismal: http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3d8ecd9b7d0e4ccd

[QUOTE=ProjectSHO89;17273346]Nonsense. According to a little birdie, returns have been less than 2% and most of them were from people who didn't know what they were doing or self-selected the wrong antenna. About 1/4 of the returns were never even assembled.

Most posters here (on AVSforum) only come on when they have problems. You rarely hear the success stories. Station engineers who received samples of the C5 to try out have reported excellent results. One even reported good results with it on VHF-5 at about 25 miles, something that was unexpected.



While the c5 may be a great antenna, the c4 was not good at all. I actually took it out of the box, and mounted it 25ft above ground, and it still
was below SECOND rate.
I beleive most posters are looking for answers, and those who respond either say... I had good results with bla bla, or I had bad results with bla bla. I value the opinions of the posters on avs forums, and once in a blue moon will you get a station engineer to respond...

Just took down a huge HD8200P and added an 2nd XG91 (all stations I want are now UHF). I now have a vertical stack with the two XG91s about 4' apart. They are combined on the mast and feed a Winegard AP-8275. I expected a BIG improvement over 1 XG91, but see only a very small improvement (a few % maybe). I used equal length 6' RG6 to the combiner (http://www.directdepot.net/product_i...ducts_id=22826) to the preamp. Maybe horz. stack is better but vert. was easy because I had a 4' mast to add. Shouldn't I see a bigger improvement??
I can't get the link to work. Is your combiner one of these?:
http://www.directdepot.net/advanced_search_result.php?search_in_description=1&keywords=combiner&categories_id=&Submit=Search

The maximum theoretical improvement is 3 dB. When I combined two CM4221 UHF antennas for CH 15 I measured 2.5 dB gain using selected baluns. When two baluns are used they must be phased correctly. If you measure less gain then try reversing the 300 ohm connections on one of the baluns. I don't know what the feed connection for the XG91 is......I think it has an integral black balun box. Combining two antennas with a splitter/combiner is an "iffy" proposition. Sometimes it works; sometimes it doesn't:
http://www.hdtvtruckee.com/
http://www.hdtvtruckee.com/CombinerMeasurement.htm
http://www.hdtvtruckee.com/CombinerComparison.htm

You didn't say what equipment you are using to measure the percentage, but it's an arbitrary scale that varies according to the equipment used. When I calibrated the signal strength scale on my Apex DT502, using the method described in the Kelvin link in my signature, I got this (compare the 3 dB attenuator steps with the percentage change on the strength scale):
http://www.avsforum.com/avs-vb/showthread.php?p=15414426#post15414426
http://www.avsforum.com/avs-vb/showthread.php?p=15790650#post15790650

There is also a signal meters ... true lies? thread:
http://www.avsforum.com/avs-vb/showthread.php?t=1146498
Maybe horz. stack is better
Horizontal stacking is more popular because it narrows the horizontal beamwidth (as in the 4228 vs the 4221). So, even if you don't end up with more gain, the narrower horizontal beamwidth often reduces multipath errors which makes it easier for the tuner to maintain lock on a weak signal.

Edit: ProjectSHO89 in the next post gives a link to some good ideas by Piggie about gain and other characteristics of antennas; don't miss it!

Nonsense. According to a little birdie, returns have been less than 2% and most of them were from people who didn't know what they were doing or self-selected the wrong antenna. About 1/4 of the returns were never even assembled.

Most posters here (on AVSforum) only come on when they have problems. You rarely hear the success stories. Station engineers who received samples of the C5 to try out have reported excellent results. One even reported good results with it on VHF-5 at about 25 miles, something that was unexpected.



While the c5 may be a great antenna, the c4 was not good at all. I actually took it out of the box, and mounted it 25ft above ground, and it still
was below SECOND rate.
I beleive most posters are looking for answers, and those who respond either say... I had good results with bla bla, or I had bad results with bla bla. I value the opinions of the posters on avs forums, and once in a blue moon will you get a station engineer to respond...


How ironic that I just came across this post on another forum: http://www.dtvusaforum.com/dtv-hdtv-reception-antenna-discussion/9301-antenna-gain-ultimate-measure-better-antenna.html

Must be a blue moon!

While the c5 may be a great antenna, the c4 was not good at all. I actually took it out of the box, and mounted it 25ft above ground, and it still
was below SECOND rate.
I beleive most posters are looking for answers, and those who respond either say... I had good results with bla bla, or I had bad results with bla bla. I value the opinions of the posters on avs forums, and once in a blue moon will you get a station engineer to respond...

I'm pretty happy with my C4. Despite being an attic mount, I get the Albany UHF stations pretty well even though they're over 66 miles away. Sure, there are better UHF antenna's out there, but for the size it's pretty hard to beat the C4. In fact on a good day, I've even gotten WYNE and WFUT, which based on my TVFool results is pretty impressive:

http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3d8ecdbb879d1a14

Of course YMMV.

Thanks rabbit73 for all the information. I assumed adding another antenna would be a no brainer if I was careful to align them. Your correct the link doesn't work... it is a Channel Plus 2532. The XG91's have a black box balun with 75ohm output. I see the tilt is off a little but other then that they are directly vert. with the driven elements the same distances from the mast. I will do some more reading...I had just the upper one before which just could receive a CBS channel I wanted but with many dropouts. At the lower position it couldn't see CBS at all. Guess it makes sense that if I run the upper XG91 through a combiner my total signal for that channel will drop.

I got the WG 7697P up and running.

http://kevinallenmoore.com/photo/d/81845-2/IMAG0054.jpg

Used my laptop running Win 7 RC1 media center and the Pinnacle 800e usb tuner and a short run of coax to dial it in. Much better than running down the ladder and inside between adjustments.

I am a little disappointed, though I am not sure the antenna is doing anything wrong. I think I am in a worse area than I thought, at least as it pertains to the fringe channels I thought I would get.

In short, I think I have quite a few channels that aren't LOS, contradicting TV Fool (http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3d8ecd4ed4d356de). The reception results that I got did not correlate with antenna alignment, at least as far as my understanding that all of my channels were available LOS at 15 feet.

The Boston CW and ION that I wanted to receive, nay, expected to receive and why I purchased a high gain antenna like this, were too weak, even pointed directly at the Boston towers.

We tried clocking the antenna at as many discrete positions as we had time for, with the rapidly fading light last night. We let Media Center run through the signal strength loop each time we moved the antenna. The best overall reception seemed to be pointing at the only real open spot out of my neighborhood, or about 300°. As a refresher I was expecting to receive the strong RI stations @ 41° and the weaker Boston stations at 28-29° while pointed at ~32°. Well, how about 300? And surprisingly I get RI CW from 83° and ION from 258°. I think I have a multipath problem, no? I did get Boston CW best as LOS I think, but "best" was only 3 out of 6 bars which I know would never be reliable enough to bother with. And Boston ION never came up over 1 or 2 bars.

Do I need to add height? An amp? Experiment more with aim? Should I have gotten the 14 foot 7698P, after all that deliberation???

I think trees and maybe some roofs of houses may be in the way, but definitely big pines.

I know the Winegard antennas suffer during shipment (and possibly manufacture) and after doing some reading I am going to take a close look at the crossover/balun box and make sure the prongs are making contact with the wires. I am also going to straighten all the elements, even the ones only slightly bent.

Overall I get more channels than before, but instead of the 24 I thought I'd get, I am down around 19 or so.

See that tree that the antenna is pointed right into? You don't need a bigger antenna or an amp, you need a STIHL! Make firewood out of it!

If you can, try re-locating the antenna towards the left (of the photo) so it isn't staring right into a nearby tree.

I think trees and maybe some roofs of houses may be in the way, but definitely big pines.


I've got an 18" Husqvarna and a pickup.
PM me the details and I'll be over on Sunday to take down all those trees and haul away the hardwood logs.
And THANKS!!

I would try a low gain preamp and try with the computer a larger distance from the antenna. The next step would putting the antenna 6-10 feet above the peak of the roof.
John

I think trees and maybe some roofs of houses may be in the way, but definitely big pines.
Thanks for the photo, Kevin. It gives us a good idea of what's going on.

I quote Ken Nist, KQ6QV, from his hdtvprimer site (which seems to be down at the moment, otherwise I would have given links):

Trees as obstructions -

A tree has very little effect on VHF-low, but a significant effect on VHF-high. But the big problem is UHF. A tree with leaves blocks about 90% of a UHF signal. The space behind the tree is an overlap of the signal going through the tree and the signal diffracting around the tree. Such overlapping fields have an alternating pattern of strong and weak spots separated by only a few feet. An antenna in a strong spot might work nicely until the wind blows, deforming the tree and moving the spots. Thus, for DTV stations, you are likely to see dropouts when the wind blows. Even in a good-signal neighborhood it is inadvisable to put a UHF antenna behind a tree.

If the tree loses its leaves in the fall, reception behind it will improve dramatically. Many people get a TV for Christmas, and erect an antenna for it in January, and then wonder why it quit working in May. It’s the trees.

The farther away a tree is, the less of a problem it is. For far away trees, assume no signal penetrates the tree, and reception will be by diffraction around the tree. See Diffraction.

Trees block 100% of satellite signals.

I'm pretty happy with my C4. Despite being an attic mount, I get the Albany UHF stations pretty well even though they're over 66 miles away. Sure, there are better UHF antenna's out there, but for the size it's pretty hard to beat the C4. In fact on a good day, I've even gotten WYNE and WFUT, which based on my TVFool results is pretty impressive:

http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3d8ecdbb879d1a14

Of course YMMV.

My problem with the c4 was not uhf, but it's claim to be a vhf antenna. Probably works los within 40 vhf miles...

I had picked out the Avermedia Duet since I want a dual tuner with internal splitter. Any thoughts on that one? It is fairly new as well. Newer than the other competing dual tuner on the market, the Hauppauge 2250 (which also does NTSC).
Yeah, the Avermedia Duet is really recent and should have 6th gen tuners in it as well.

Like everyone else says, those trees are a huge obstacle for you. When the leaves fall, will there be any clear line thru them ?

The next step would putting the antenna 6-10 feet above the peak of the roof.
I would go about 30 - 40 ft above the roof with guy wires to clear the trees. (or are they even higher than that ?) The WG 7697P doesnt look heavy or like it would have a lot of wind load.

I removed a few of the problem branches from the leafy tree closest to the antenna. As I also mentioned I had 4 very large white pines removed from my front yard only a few weeks ago. It was a very big job...I have those pictures elsewhere on my gallery if anyone is interested :D

Here are all the pictures of how the antenna is currently aimed. It is about 308 degrees. My signals of interest are between 28 and 41...so obviously something is going on. I took a picture at what I thought would have been my ideal aim, about 32 degrees. As you can see I did remove some of the problem leaves. I also plan to take the entire tree down but the rest of the trees are large white pines that are gonna cost probably $600 or $700 each to remove, and they're not mine.

http://kevinallenmoore.com/photo/v/misc/ATSC/

It is about 308 degrees. My signals of interest are between 28 and 41...so obviously something is going on.
Your stations at 41 degrees are very strong, above 47 NM for the most part, so no surprise getting those just about any way the antenna is pointed.
Can you get channel 9 and 26 at 265/274 degrees now ?

I don't think so. I recall 29 coming in while I was on the roof but I don't think the current aim is ideal for that.

I do get CW, 28.1 from 83° at 4/6 bars and ION 69.1 from 258°. My original plan was to somehow receive these. Unfortunately, I lost a Boston ABC 5.1, PBS 2.1 and independent 38.1, while aimed at my current 308°. If I aim towards Boston I get the channels back that I lost but then I get no CW or ION...boston or otherwise. The two Boston versions I thought I'd get.

I went back on the roof last night and tried to straighten the elements. I looked up at the antenna this morning and I could still do a better job.

I also removed the crossover box and bent the prongs inward a bit so they grab the wires a little better. That didn't seem to make a difference, though perhaps I should put the antenna back at 32° after I get that tree down and see what happens.

One more thing...is there any reason I should persue the exchange of 7697P for the 7698P? It has 1.6dB more gain at RF 32, which was the Boston ION that I had such trouble with. From RF 25 to 40 the 7698P provides 1dB or more of increase from 7697P. Should I bother or are my environmental and/or geographical issues much bigger?

Wow that is a bad area. What is your antenna height?

Also I looked up those antennas. They are pretty high gain. How much do you think you lose by splitting? And do you have them pointed in the same direction? You have a lot of stuff at 90d but not everything.

You know what else I realized...you probably don't need a fancy band pass/cut combiner. You might even be able to use a splitter backwards. What do you use?

If this is a response to my last post, the uhf is at about 25 ft AGL and the VHF is mounted 4 ft below. I didn't use a combiner I wired the YA 1713 to the VHF terminals on the HD 9022 with quad cable and CM baluns and then the HD-9022 to the preamp. I wasn't worried about losses from the YA-1713 as we have no problem getting the VHF signals, just the UHF. I think the CM baluns have about 0.5 db loss, so I might have lost 1 db as it takes 2 to connect. I suppose I could have used shielded 300 ohm and had no loss, but it wasn't worth the trouble tracking down a couple of feet of 300 ohm. See the attached photo below.

I pick up the major Philly networks (including ch 6) as well as the NYC networks and the array is pointed at NYC. Lots of trees in the way plus 2 or 3 ridges. We are the only people in our neighborhood still using OTA. I may add another HD 9022 to improve WOR and WNYW reception and maybe eliminate the multipath interference we get when aircraft fly over as we are on a major flight path to NYC and Newark and probably Philly. But that's next year's project.


OZ

Hmm that makes me wonder if I end up having to raise mine, if I should relocate it to the chimney or just put a longer mast on where it is now.

Just took down a huge HD8200P and added an 2nd XG91 (all stations I want are now UHF). I now have a vertical stack with the two XG91s about 4' apart. They are combined on the mast and feed a Winegard AP-8275. I expected a BIG improvement over 1 XG91, but see only a very small improvement (a few % maybe). I used equal length 6' RG6 to the combiner (http://www.directdepot.net/product_i...ducts_id=22826) to the preamp. Maybe horz. stack is better but vert. was easy because I had a 4' mast to add. Shouldn't I see a bigger improvement??

4 feet is too far apart, they should be 1 wave length apart - ch 14 is about 25 inches measured from boom to boom. Also your connecting cables have to be exactly the same length and your baluns have to be in phase with each other. Its always good to test your antennas on the ground before putting them up. I drove a section of rebar into the ground and slipped the mast onto it for my testing, worked great.

Good luck,

OZ

"Optimum" separation for Horizontal Stacking is a function of the antenna's
boomlength (or beamwidth) and would be MORE than one wavelength:
http://vk1od.net/antenna/dl6wu/EstimatingBeamwidth.htm
http://vk1od.net/antenna/dl6wu/
http://www.ifwtech.co.uk/g3sek/stacking/stacking2.htm#DL6WU
http://www.grantronics.com.au/docs/StkYagis.pdf

Of course, bear in mind that wavelength for Ch14 is much larger than Ch51,
with lower gain and higher beamwidth. So decide where to optimize....

Hmm that makes me wonder if I end up having to raise mine, if I should relocate it to the chimney or just put a longer mast on where it is now.
What you should do is to experiment with the height, looking for the sweet spot. At UHF, even 6 inches can make a difference. And experiment with the height at the time of day you do most of your viewing, probably early evening, like when you took the picture.
Also, what condition is your coax in ? Also, maybe try another balun.

"Optimum" separation for Horizontal Stacking is a function of the antenna's
boomlength (or beamwidth) and would be MORE than one wavelength:
http://vk1od.net/antenna/dl6wu/EstimatingBeamwidth.htm
http://vk1od.net/antenna/dl6wu/
http://www.ifwtech.co.uk/g3sek/stacking/stacking2.htm#DL6WU
http://www.grantronics.com.au/docs/StkYagis.pdf

Of course, bear in mind that wavelength for Ch14 is much larger than Ch51,
with lower gain and higher beamwidth. So decide where to optimize....

Very nice links the last one in particular as it has a good explanation of phasing. My choice of 1 wavelength came from much searching and a couple links basically said start at 1(reflectors can't touch) and adjust as needed. I can't find the link though so I can't post it.

Your references seem to be all related to HAM radio, and I am not sure if it is absolutely applicable to UHF antennas, especially if someone is stacking the bow-tie types. Here's some more links:

http://www.digitalhome.ca/forum/showthread.php?t=41102&page=2

http://www.digitalhome.ca/forum/showthread.php?t=107432

http://www.hdtvprimer.com/ANTENNAS/ganging.html#TAT

Hope this helps.

OZ

The statement from the grantronics.com stacking link of "you should stack at a distance in wavelengths of 57 / 3dB beamwidth in degrees." applies to any antenna at any frequency.
John

What you should do is to experiment with the height, looking for the sweet spot. At UHF, even 6 inches can make a difference. And experiment with the height at the time of day you do most of your viewing, probably early evening, like when you took the picture.
Also, what condition is your coax in ? Also, maybe try another balun.

Wow 6 inches huh?

The coax is all brand new quad shield with compression F connectors installed by yours truly. The only variable is the way I made the connections. The foil would slide back and get crushed down. But comparing to the 8 footer I was using on the roof that was terminated by a cable guy, there is very little signal loss, including the fact that the run probably approaches 60 or maybe even 70 feet.

I bought a balun for my old antenna when I upgraded to the coax from the 300ohm. But this Winegard balun includes crossover circuitry to combine the VHF and UHF sections of the antenna, so I don't know if I could use a conventional balun.

Yeah, the Avermedia Duet is really recent and should have 6th gen tuners in it as well.

Well if I am really lucky it will have better sensitivity and performance than my single USB tuner. But I dunno if I feel lucky.


Like everyone else says, those trees are a huge obstacle for you. When the leaves fall, will there be any clear line thru them ?

The only leafy tree in close proximity to the antenna is the one in the first picture. I have limbed it since and will get rid of it soon enough. The rest are very large white pines, mainly trunks.


I would go about 30 - 40 ft above the roof with guy wires to clear the trees. (or are they even higher than that ?) The WG 7697P doesnt look heavy or like it would have a lot of wind load.

Whoa, above the trees? I don't think that is going to happen. If that's what I need then I will have to say goodbye to certain channels. I never meant for this project to get that complicated and expensive.

It's not heavy, though I am wondering if I should upgrade to the 14 foot version, the 7698P. I just don't know if it's worth the hassle. I think getting the antenna in the path of the signal is worth a lot more than a little higher gain antenna placed sub-optimally. Then again, I could do both...

At UHF, even 6 inches can make a difference.Absolutely!! I've seen only 6 inches make a huge difference with UHF.

It's not heavy, though I am wondering if I should upgrade to the 14 foot version, the 7698P. I just don't know if it's worth the hassle.
Hmm, I think your better off spending the money on a quality low noise preamp to make up for the 60 - 70 feet of cable (plus the inevitable splitters, heh).

The statement from the grantronics.com stacking link of "you should stack at a distance in wavelengths of 57 / 3dB beamwidth in degrees." applies to any antenna at any frequency.
John

"you should stack at a distance in wavelengths of 57 / 3dB beamwidth in degrees." This may be true, but WTF does it mean to us poor non-engineers? It's wonderful to have highly trained people adding their knowledge here, but when you do why not lay it out in terms anyone can understand? Like in the case of the XG-91 question why not just give the guy the calculation's results? And then maybe go step by step with that antenna as the basis.

Just a thought.

OZ

The only info I could find on the XG91 BW is a statement that it is about 23 degrees. If that is at the old channel 69 near 800 Mhz, a wavelength is 37.5 cm. The spacing would come out 93 cm.
John

The only info I could find on the XG91 BW is a statement that it is about 23 degrees. If that is at the old channel 69 near 800 Mhz, a wavelength is 37.5 cm. The spacing would come out 93 cm.
John

That seems too close to me. The middle of the UHF band is now channel 33 at 599 MHZ. That sets the spacing at about 4'.

You also have to take into account the beamwidth which will usually be wider at a lower channel. In fact for most UHF antennas if you calculate the spacing for one channel, it will be the same for other channels.
John

I got the WG 7697P up and running.

I am a little disappointed, though I am not sure the antenna is doing anything wrong. I think I am in a worse area than I thought, at least as it pertains to the fringe channels I thought I would get.

The Boston CW and ION that I wanted to receive, nay, expected to receive and why I purchased a high gain antenna like this, were too weak, even pointed directly at the Boston towers.

We tried clocking the antenna at as many discrete positions as we had time for, with the rapidly fading light last night. We let Media Center run through the signal strength loop each time we moved the antenna. The best overall reception seemed to be pointing at the only real open spot out of my neighborhood, or about 300°. As a refresher I was expecting to receive the strong RI stations @ 41° and the weaker Boston stations at 28-29° while pointed at ~32°. Well, how about 300? And surprisingly I get RI CW from 83° and ION from 258°. I think I have a multipath problem, no? I did get Boston CW best as LOS I think, but "best" was only 3 out of 6 bars which I know would never be reliable enough to bother with. And Boston ION never came up over 1 or 2 bars.

It's the trees. The signals can't go thru the trees, so they are diffracted around them giving you antenna aim that is not towards the transmitters. If you could somehow gradually increase the height of your antenna, you would begin to see your azimuth readings match the ones in the tvfool report. (Where's that friend with a "cherry picker" truck when you need him?)
In short, I think I have quite a few channels that aren't LOS, contradicting TV Fool (http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3d8ecd4ed4d356de). The reception results that I got did not correlate with antenna alignment, at least as far as my understanding that all of my channels were available LOS at 15 feet.
Tvfool is sometimes wrong, but not in this case. It has to make some assumptions, one of which is that there are no trees directly in front of the antenna.
Overall I get more channels than before, but instead of the 24 I thought I'd get, I am down around 19 or so.
I think you are doing very well considering the location of the antenna.:)
Do I need to add height? An amp? Experiment more with aim? Should I have gotten the 14 foot 7698P, after all that deliberation???Yes, you need to add height....as much as possible and away from the trees as much as possible.

A preamp will make up for the loss in the coax downlead (as 300ohm said) but it will not make up for a poor antenna location.

The aim experiments that you have already done have told you that the trees are in the way.

The 7698 is not the best solution for your problem. Its gain is only slightly more than the 7697 and it is a lot harder to handle up in the air. Actually, I initially imagined that you would end up with the 7696. An antenna smaller than the 7698 mounted up-in-the-air in an open location will out perform the 7698 in your present antenna location.

Many times I have measured a signal increase of more than 10 dB after moving an antenna to a better location.
I think getting the antenna in the path of the signal is worth a lot more than a little higher gain antenna placed sub-optimally.Correct!:D

The hdtvprimer site seems to be working now. Take a look at the neat diffraction diagrams:
http://www.hdtvprimer.com/ANTENNAS/siting.html

That tree is killing your reception.

Can you relocate the antenna to the other end of the house (towards the far front corner looks like it would be better)? Try to get at least 6' above the roof peak (10' would be better).

I would think that vertical stacking would work better for you than a pre-amp.

"you should stack at a distance in wavelengths of 57 / 3dB beamwidth in degrees." This may be true, but WTF does it mean to us poor non-engineers? It's wonderful to have highly trained people adding their knowledge here, but when you do why not lay it out in terms anyone can understand? Like in the case of the XG-91 question why not just give the guy the calculation's results? And then maybe go step by step with that antenna as the basis.

Just a thought.

OZ
The first link has the answers in pretty simple terms:
http://vk1od.net/antenna/dl6wu/EstimatingBeamwidth.htm
Fig 1 shows how Yagi Beamwidth can be derived from Gain (and vice versa).
Fig 3 charts the optimum separation Distance vs Antenna Gain, which will
VARY with frequency in most antennas....chose which freq or channel to optimize.

Gain vs Channel is given here (or in manu. specs):
http://www.hdtvprimer.com/antennas/comparing.html
Converting between Channel and Freq isn't even required.

The first link has the answers in pretty simple terms:
http://vk1od.net/antenna/dl6wu/EstimatingBeamwidth.htm
Fig 1 shows how Yagi Beamwidth can be derived from Gain (and vice versa).
Fig 3 charts the optimum separation Distance vs Antenna Gain, which will
VARY with frequency in most antennas....chose which freq or channel to optimize.

Gain vs Channel is given here (or in manu. specs):
http://www.hdtvprimer.com/antennas/comparing.html
Converting between Channel and Freq isn't even required.

Clear as mud.

OZ

For Ray50 or any XG91 users here's some links:

http://hdtv.forsandiego.com/messages/4364/5643.html

http://www.dbstalk.com/showthread.php?t=9676

http://www.digitalhome.ca/forum/showthread.php?t=107432

Good luck,

OZ

For Ray50 or any XG91 users here's some links:


http://hdtv.forsandiego.com/messages/4364/5643.html

http://www.dbstalk.com/showthread.php?t=9676

http://www.digitalhome.ca/forum/showthread.php?t=107432

Good luck,

OZ
Thanks for the interesting links. But, in the third link stampeder has it backwards about vertical and horizontal stacking vs beamwidth (unless he does an edit):
http://www.digitalhome.ca/forum/showpost.php?p=933732

He should have said that vertical stacking reduces the vertical beamwidth and horizontal stacking reduces the horizontal beamwidth. I hope he doesn't think that the DBGH has narrow horizontal beamwidth:
http://www.avsforum.com/avs-vb/showthread.php?p=14937123#post14937123 polar plots DBGH VS CM4228

http://www.hdtvprimer.com/ANTENNAS/glossaryR.html#stacked
which says:
When dipoles are stacked horizontally, the horizontal beam-width becomes very narrow. This is because they do not add in-phase for directions not straight ahead. Similarly, when stacked vertically, the vertical beam-width becomes narrower.
The same principles apply when stacking whole antennas, not just dipoles.
Narrower beamwidths shown here:
http://www.hdtvprimer.com/ANTENNAS/16bay.html

Ive always liked the venetian blind / horse blinders analogy found here :

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

Ive always liked the venetian blind / horse blinders analogy found here :

http://www.kyes.com/antenna/stackluge.html
And I like that link.
Thanks.

Here are a couple of tests I conducted last year between a single XG91 and two Triax Unix 100s (almost identical to the XG91) horizontally stacked.
http://www.wtfda.info/showpost.php?p=6610&postcount=1
http://www.wtfda.info/showpost.php?p=6715&postcount=13

If you have multipath issues and plan to stack, stack them horizontally.
http://atechfabrication.com/tests/03-03-02_horizontal_vs_vertical_stacking_test.htm

Great discussion here about stacking XG91s.
http://www.avsforum.com/avs-vb/showthread.php?t=1182277
MAX HD and cpcat have built and tested a number of various configurations with many different brands/models of antennas. My antenna setup came from MAX HD.

Steve

Theyre getting better. I recently got a (open box at Newegg, $37) AVerTV Bravo Hybrid PCI-E which has a 6th generation tuner. Directly testing it on the same line, and at the exact same time as my Zenith DTT901 CECB, the PCI-E card drops out just a millisecond before the DTT901 does on a weak signal. And its about a millisecond slower to recover.
Actually, thinking it about it a little more, the pc tuner gets sound and video about a millisecond behind the regular tv (other pc tuners I played with do the same). So its really recovering from a drop out at about the same time.

And I like that link.
Thanks.

Ive always liked the venetian blind / horse blinders analogy found here :

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

Yes, great link and it even has the most direct answer to my particular problem , multipath from aircraft:

"Vertical stacking improves both gain and vertical directivity. This helps reduce airplane flutter and attendant picture roll"

This may also be the original source for the post I read somewhere about vertical stacking 1 wavelength apart:

" 0ptimum and minimum spacing is 0.94 and 0.60 wavelength, respectively, at the lowest frequency received. Spacing exceeding one wavelength reduces the performance of the stack."


After wading through all these new links I remembered this one:

http://www.wtfda.org/index.php?option=com_content&task=category&sectionid=5&id=24&Itemid=43

Read the link to Stagger Stacking, it takes things to a whole 'nutha level 8^)

OZ

Cut down two trees and aggressively limbed the big white pine. I played the aim-game again with the laptop on the roof. I ended up at about 50 degrees which is almost exactly where the old antenna was aimed. Seems like the best overall trade off. I get a Boston CBS, ABC and FOX. And I get the off axis RI CW and RI ION. Boston 38 is intermittent but all of this is better than the 300 degree aim I said I was using earlier.

I know I need to raise it and I will. But something still confuses me. I mentioned I get Boston Fox 25. I also get another channel, 46. Well, the Boston ION and CW that I just can't get at all (not even a little) are supposedly stronger than these other two channels, according to TV Fool. And specifically 38, which is somewhat intermittent, is supposed to be stronger than Boston CW. What's up with that?

Cut down two trees and aggressively limbed the big white pine. I played the aim-game again with the laptop on the roof. I ended up at about 50 degrees which is almost exactly where the old antenna was aimed. Seems like the best overall trade off. I get a Boston CBS, ABC and FOX. And I get the off axis RI CW and RI ION. Boston 38 is intermittent but all of this is better than the 300 degree aim I said I was using earlier.

I know I need to raise it and I will. But something still confuses me. I mentioned I get Boston Fox 25. I also get another channel, 46. Well, the Boston ION and CW that I just can't get at all (not even a little) are supposedly stronger than these other two channels, according to TV Fool. And specifically 38, which is somewhat intermittent, is supposed to be stronger than Boston CW. What's up with that?

Keep in mind that the terrain modeling and signal power forecasting software has limitations that affect accuracy.

Two things in particular may apply:

1) Terrain resolution. The TVfool software divides the terrain into 100 square meter blocks and averages the terrain within that block and between adjacent blocks. That makes the resultant estimates highly variable for the "last mile" or so of the signal path. Other online modeling, notably at the FCC's website, is 10 times coarser in its resolution.

2) TVFool's (and any other forecast based on the LRI model) software assumes that you have clear line-of-sight to the horizon. No trees, no buildings, etc, can be forecast. if you have these, then the accuracy of the forecast becomes poorer very quickly

In other words, don't expect the forecasts to be 100% accurate....

I don't expect total accuracy but I did expect consistency. When the towers are in the same general area I figured I could at least reference tv fool on a relative level.

You could have an issue with the proper location of the antenna height to RF wavelength wave peak.

Follow this link "Erecting a TV antenna" at http://www.hdtvprimer.com/ , then follow this link "Choosing a mounting site."

I don't expect total accuracy but I did expect consistency.
I experience similar anomalies here in southern NH. 38 (WSBK) and 44 (WGBX) are much worse then stations modeled weaker. Channel 7 (WHDH) and 25 (WFXT) come in all the time even though they model 5 and 10 dB lower then WGBX.

http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3dbefb1d6ecdfd6f

We have a similar situation antenna is about 30 feet AGL which places it below treetop level.

I don't expect total accuracy but I did expect consistency. When the towers are in the same general area I figured I could at least reference tv fool on a relative level.

Even signals from antennas on the same tower might vary significantly in actual signal quality due to variables related factors other than power.

Additionally, TVF uses FCC license and permit data, If a CP has been issued, TVF uses the to-be-built data as soon as the CP is issued. In real life, stations actually have a lot of time to build the facility that is permitted leading to a falsely optimistic forecast for that station.

IOW, take it as a guide, but not an absolute.

In my own case, my TVF isn't too bad: http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3dbefb2e2ee8e241

However, in real life, my signal from KETC is dismal and KDNL isn't much better off my 4-boom 91XG at 35' AGL. KMOV, however, is very strong compared to most of the others.

In real life, stations actually have a lot of time to build the facility that is permitted leading to a falsely optimistic forecast for that station.
Yep, and the stations do testing and tweaking right after the transmitter is operational, which can drive you nuts for a while, heh.

In real life, stations actually have a lot of time to build the facility that is permitted leading to a falsely optimistic forecast for that station.
Yep, and the stations do testing and tweaking right after the transmitter is operational, which can drive you nuts for a while, heh.

....and they don't tell the public what they're doing so the frustrated user is left thinking it's a problem with the receiving equipment.....

You could have an issue with the proper location of the antenna height to RF wavelength wave peak.

Follow this link "Erecting a TV antenna" at http://www.hdtvprimer.com/ , then follow this link "Choosing a mounting site."

Someone else posted that link before and I looked through it. Very illuminating.

I experience similar anomalies here in southern NH. 38 (WSBK) and 44 (WGBX) are much worse then stations modeled weaker. Channel 7 (WHDH) and 25 (WFXT) come in all the time even though they model 5 and 10 dB lower then WGBX.

http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3dbefb1d6ecdfd6f

We have a similar situation antenna is about 30 feet AGL which places it below treetop level.

Mine is actually only 15 feet and I have a fairly close and tall tree line. So I suppose I should be happy with what I have. Many of them will lose their leaves over the next few months so we'll see what happens. Could be very interesting.

Interesting about 38 and 44. They both have troublesome reception for me, as well. 7 sometimes gives me good signal strength numbers but doesn't want to actually work...could be interference. 25 works nicely now. How about your Boston CW or ION, 56.1 and 68.1?

Even signals from antennas on the same tower might vary significantly in actual signal quality due to variables related factors other than power.


I find TV Fool fairly accurate other than a couple of anomalies toward the fringe end of my list. I suppose that's why I was frustrated when it turned out to be less than 100% accurate.

Your reception discussion prompts my question.
I have a Wineguard PR-8800 and a CH3 only joined by UHF/VHF only connector/Joiners. Then thru a Wineguard HDP 269.
All Ch were UHF and one CH 3. all was well.
This week CH 34 switched to CH 13 and Reception dropped from 100% to 76% (on a DTV PAL DVR an over the air only HD DVR). The old analog from 13 could be picked up with a paper clip antenna.
My local Forum (Roanoke VA) had a comment that covering the small space between the two identical 11 step lader like reflectors with a 'mesh' would improve CH 13 reception on the PR-8800.
Any theoritical basis for this?
Also do I
1. lay a small strip over the approx. 1" gap
2. or cover the total two reflectors
3. Just connect each of the 11 ladder steps to its mate.
It is in the attic- easy to modify.
Thanks, I am not on here often but follow it every day.
Bernieoc

Interesting about 38 and 44. They both have troublesome reception for me, as well. 7 sometimes gives me good signal strength numbers but doesn't want to actually work...could be interference. 25 works nicely now. How about your Boston CW or ION, 56.1 and 68.1?\
56 (WLVI) and 68 (WBPX) are problematical but not as bad as bad as 38 and 44. 56 comes in most of the time 68 about 50%. WLVI and WBPX both have DT-APPs to increase power so they ought to get better if that happens.

WHDH (RF 42) comes in all the time. I'm really glad they are staying on UHF. We have sperate VHF and UHF antennas. With WHDH on UHF we have no need for rotor. UHF points to Boston and VHF aimed at WENH. WMUR is a little off axis but it so strong it doesn't matter. We even get WMTW (RF 8) out of Maine on occasion.

The other stations WMUR (RF9) WENH (RF11) WGBH (RF19) WCVB (RF20) WBX (RF30) WMFP (RF18) WHDH and WFXT (RF31) all come in fine.

WPXG (RF21) the ION station out of NH comes in great but it requires use of rotor so we typically don't bother.

Here is a link to my setup:
http://www.tschmidt.com/writings/Design%20and%20install%20outdoor%20TV%20antenna.htm

Wow you documented everything! Very nice job. I ought to follow your example...

56 (WLVI) and 68 (WBPX) are problematical but not as bad as bad as 38 and 44. 56 comes in most of the time 68 about 50%. WLVI and WBPX both have DT-APPs to increase power so they ought to get better if that happens.

I hope that, combined with raising my antenna a few feet, will allow me to receive them. Though right now it is not looking like I need WLVI as I get the off axis RI one. And I get the REALLY off axis ION but only Boston's WBPX promises some HD content (68.1 says 720p). But no such thing as too many channels, especially free HD OTA ones.


WHDH (RF 42) comes in all the time. I'm really glad they are staying on UHF.

Ah, so are they RF 42 then? There is some weirdness associated to WHDH from what I've seen. First, both my Vista and Win 7 Media Centers say 7.1 is not the main channel...something about temp authority. And like I said, 7.2 shows signal but no picture. When I look at my Silicon Dust lineup (http://www.silicondust.com/hdhomerun/lineup_web/US:02852#lineup_914406), it shows a conflict for WHDH. Suggests RF 42 OR RF 7. And TV Fool says RF 42 for WHDH but lists no vChan ID!! So perhaps my problem is I need to manually tell my media centers what the deal is then it may work.

I'm looking for a longer mast and I'd probably get another 3 feet or so with this (http://www.summitsource.com/antenna-mast-tv-9-pole-pipe-85-ft-after-interlock-20-gauge-steel-tube-outdoor-rooftop-offair-2-part-interlocking-support-p-6876.html). I can't find anything longer and there is just not much out there overall. Am I looking in the wrong places?

I'm looking for a longer mast and I'd probably get another 3 feet or so with this (http://www.summitsource.com/antenna-mast-tv-9-pole-pipe-85-ft-after-interlock-20-gauge-steel-tube-outdoor-rooftop-offair-2-part-interlocking-support-p-6876.html). I can't find anything longer and there is just not much out there overall. Am I looking in the wrong places?

I used a chain link fence pole from home depot. Maybe not the best solution, but it worked for me. There are various diameters depending on if you get railings or posts so I made sure it was sturdy enough for my length of mast. Some are obviously too thin and flexible but others are quite sturdy.

Yeah that is a good point. It's just hollow tubing. It doesn't have to be "antenna mast" pipe, which is really no different from any other kind of tubing.

I make up masts from here: http://www.dxengineering.com/Products.asp?ID=279&SecID=136&DeptID=43
John

How do you join the lengths of 6 feet? The only thing I am familiar with would be a band exhaust clamp made for butt connections. Something like a 2" one of these (http://www.summitracing.com/parts/WLK-33228/) or a 1" one of these (http://www.summitracing.com/parts/WLK-35200/). I'd need something between these sizes probably.

EDIT: Nevermind. You stack different diameters on each other, with the bottom obviously being the largest, and use their clamps. They look like regular hose clamps but I assume they are designed to hold the shaft from spinning in bad weather.

Do you think 1.5" for the bottom 6 feet and 1-3/8 for the top 6 feet is enough to hold up an 11 foot antenna like my Winegard 7697P?

Additional ways to NOT receive OTA signals:
http://www.tvtechnology.com/article/88182

1) Indoor Passive Antennas were found to have Gains ranging from -6 dBd down to -15 dBd....or worse.
[MUCH WORSE THAN WHAT MOST ANTENNA MEASUREMENTS INDICATE.....]
[Perhaps they were referring to UHF-only antennas??? And if they were, why not say so???]

2) Indoor Amplified Antennas were NOT improving the situation and usually made it WORSE,
including amplified FM signals overloading the DTV.
[VERY UNEXPECTED AND CONTRARY TO MY EXPERIENCES.]
BTW: Second harmonics of FM stations interfere with Hi-VHF Ch7-13....not UHF.

3) People were "hiding" the antenna behind the TV or AV-Gear stack.
[DUH!!!! GUARANTEED TO KILL WHAT LITTLE SIGNAL THERE MIGHT BE....]

4) Interference from the AV-Gear, fluorescent lights, cordless phone base stations, et.al.
was frequently a problem....Part 15 rules should be reviewed.
[Q: WHERE'S THAT IN THE SETUP INSTRUCTIONS??? A: Just after the lightning warning???]


5) Location, Location, Location....moving the antenna HIGHER was generally better.
[BUT WATCH OUT IN APTs/CONDOs BECAUSE YOUR "ROOF" MAY CONTAIN METAL REBAR.]

6) Leakage of Cable TV signals were sometimes interfering with OTA reception.
[COULD BE DIFFICULT TO TROUBLESHOOT.]

7) People were confused by the ill-conceived "virtual channel" confusion and were NOT
aware that the REAL channel might be in a different band and require a different antenna.
[DUH....ANTENNA DISCUSSIONS WERE [B]MISSING IN THE PSAs!!!!]