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The Official AVS Antenna and Related Hardware Topic! - Page 51

post #1501 of 16086
Hi MAX HD, that combiner that I used was a one in & two outs
splitter that I reversed. As I said before, I will try the antennas
again, And I will let you know how it turns out. Also, I checked the
Excel document that someone else posted, and am trying to figure out
what the NEC is that the document refers to. Is that an independent
testing organization? If anybody knows, let me know.
--ALSO--I have found a great FCC web site that will let you know everything that did or did not want to know about a tv station,
including footprint & location maps. I tryed to post it yesterday,
but this forum would not let me because I don't have 5 posts yet.
When I do, I will post it then.
fay28301
post #1502 of 16086
Here is that FCC site:

http://www.fcc.gov/fcc-bin/audio/tvq.html

I have used it with pretty good luck on finding out everything you did & did not want to know about a tv station, including its footprint and maps of where it is located. All I ever do is plug in the city & state, and where it asks for the channel you want to look up, I always put ch. 2 into the lower as the upper already has ch. 69 in it. When I do it like that, it always gives me all of the stations in that city. Then I click on the one I am interested in.
fay28301
post #1503 of 16086
Quote:
Originally posted by cpcat
That's probably a pretty good preamp. I'm not sure you'd see much improvement with the CM 777x series, but you might. My 7777 gave me a small but significant improvement over a Blonder Tongue Vaulter III plus. If you decide on a new preamp, I'd get the 7777 just to have VHF capability as it's about the same cost. The performance on UHF will be the same. If your current preamp has a 300 ohm input, that may be a small advantage in not having to use a balun. The 777x series has 75 ohm inputs so you'll likely incur some minimal loss through the conversion which may offset any improvement the new preamp might give you.

What channel is giving you the problem? The Winegard 8-bay has a rep for not being very good in the upper UHF range. It's also possible the channel in question is still at low power or you have co-channel interference from an analog. Here's a computer simulated comparison of various antennas including the Winegard 8800:http://www.hdtvprimer.com/ANTENNAS/comparing.html

Assuming you're not using a rotor, the CM 4228 is pretty hard to beat for flat response up and down the UHF range. It can be hard on a rotor, though.

Thank for the reply. The channel that's giving me the biggest problem is 16-1, but it is as very low power. It did come in strong Friday and Saturday but it is raining today, so it's not coming in at all. The Blonder Tongue uses 300 ohm inputs so I might not gain with the Channel Master
(it came last Thursday but I haven't had a chance to do anything with it-CM 7775--all my local digitals are UHF--I have a cable feed for the analogs).
I was going to add another length of mast but the store was out of the 5 ft lengths. Increasing the height may help more than the new pre amp. If the 8 bay doesn't do the job (most of the towers are 40-50 miles from me in the same direction). One is full power and two are a little less than full power but I can get their signals with an indoor antenna (with some problems on one channel). The fourth channel I am trying to get is very low power (FOX). Our CBS station will finally be on the air this spring
(supposed to start up at full power).
.
post #1504 of 16086
Have you had practical experence at eliminating or at least reducing the effects of CCI between a digital and an analog signal?

Ch. 13 digital due North at 50 mi. and analog 60+ mi. at SSE
Digital nearly wipes analog out completely.

I'm an avid NFL football fan, thinking I'm now going through withdrawal shock! I'm already thinking about next season. I very much miss my analog 13 for Steelers games.

I'm thinking of a dedicated hi-band vhf or cut-to-channel 13 antenna on the south side of my house.

Any ideas?

Thanks
post #1505 of 16086
Quote:


Originally posted by bruschi88
I'm thinking of a dedicated hi-band vhf or cut-to-channel 13 antenna on the south side of my house.

http://community-2.webtv.net/GregBarker/UltraHighGain/
post #1506 of 16086
Thanks Rack!

Yes,one of these strategically placed to optimize the reception of the analog station should work nicely.The reflector design may help some too,to null out the DT station.

Have some left,ready to ship!

http://community-2.webtv.net/GregBarker/UltraHighGain/
post #1507 of 16086
Quote:


Originally posted by bruschi88
Have you had practical experence at eliminating or at least reducing the effects of CCI between a digital and an analog signal?

Ch. 13 digital due North at 50 mi. and analog 60+ mi. at SSE
Digital nearly wipes analog out completely.

...Any ideas?

The trick is to point one antenna directly at the analog source, pad it down so that its output matches that of the main antenna, and couple the two leads so that they are 180 degrees out of phase with one another.

There isn't much point in me trying to explain how one goes about balancing the two signals and coupling them out of phase with one another because you surely do not have the signal measuring equipment needed to do so, but if you really have to solve this problem, that is what you should have a local antenna expert do.

I have a high-band (7-13) adjustable phase shifter I bought from Microwave Filter Company that I could sell you that makes the job easier to do, if you are intent on giving it a shot. I think paid about $500 for it, but I could let it go for $300.
post #1508 of 16086
Oops. I now see that you are trying to preserve the analog source while canceling the digital, so do the opposite of what the above post recommends.
post #1509 of 16086
Quote:


Originally posted by bruschi88
Have you had practical experence at eliminating or at least reducing the effects of CCI between a digital and an analog signal?

Ch. 13 digital due North at 50 mi. and analog 60+ mi. at SSE
Digital nearly wipes analog out completely.

I'm an avid NFL football fan, thinking I'm now going through withdrawal shock! I'm already thinking about next season. I very much miss my analog 13 for Steelers games.

I'm thinking of a dedicated hi-band vhf or cut-to-channel 13 antenna on the south side of my house.

Any ideas?

Thanks

It's also possible to null unwanted channels by the use of horizontal stacking. I've done this with some measure of success. See http://www.kyes.com/antenna/sca/scaint1.html and
http://www.kyes.com/antenna/sca/scaint2.html

The spacing required at channel 13 for increased gain is fairly wide, but I think you'll find the spacing for nulling should be more manageable. You may have to experiment with different widths to see what works best.
post #1510 of 16086
I once significantly improved the front-to-back ratio of a highband antenna, receiving channel 7 in a hostile reception environment, by placing a second, identical highband antenna exactly one quarter wave length below it (around 29", as I recall). The front-to-back ratio increased without even electrically connecting the second antenna.

Actually, I found this by accident. I was removing and throwing away abandoned antennas on a highrise condominium with four masts, and noticed that the channel 7 got sucky when I removed the abandoned channel 9 antenna on the same mast, but improved when I clamped it back on, and then the rear rejection improved even more when I replaced the obsolete channel 9 antenna with a matching YA-1713.
post #1511 of 16086
Okay, I have a CM 4228 on order, and will also need a VHF antenna. One of the signals is just 5 of so miles away(channel 4) but the other VHFs (channel 2, 7,10) are around 50 miles. What VHF only antenna that is still being made would be good for this purpose?
Thank you
post #1512 of 16086
Quote:


Originally posted by VMsat
Okay, I have a CM 4228 on order, and will also need a VHF antenna. One of the signals is just 5 of so miles away(channel 4) but the other VHFs (channel 2, 7,10) are around 50 miles. What VHF only antenna that is still being made would be good for this purpose?

What market has 4 VHF digital signals? I suspect you're using analog channel equivalents, unless you're near Salt Lake City.

If you really need a VHF-only, this is a good one:
http://www.winegard.com/offair/pdf/hd4053p.pdf
post #1513 of 16086
They are not all digital, the channel 7 and 2 are digital but the others are not. But I need to get the analog 4 as well.
post #1514 of 16086
Quote:


Originally posted by VMsat
Okay, I have a CM 4228 on order, and will also need a VHF antenna. One of the signals is just 5 of so miles away(channel 4) but the other VHFs (channel 2, 7,10) are around 50 miles. What VHF only antenna that is still being made would be good for this purpose?
Thank you

Others to consider:
Antennacraft 3bg17:http://www.antennacraft-tdp.com/pdfs/3bg17_.pdf
3bg22:http://www.antennacraft-tdp.com/pdfs/3bg22_.pdf
cs900:http://www.antennacraft-tdp.com/pdfs/CS900.pdf
Delhi VIP 304 or 305: http://wade-antenna.com/VHF-FMantennas.htm
post #1515 of 16086
Thanks. I have another question. My parents like in the country and have a 35 foot antenna mast which is mounted in the ground about 50 feet from their house. The main tv is another 100 feet or more to the other side of the house. I think the CM 4228 is a good choice for UHF since some of the stations are atleast 50 miles or so away. However, one of the stations is only about 5 miles away from their house. My question is if a CM 7777 preamp is used, as the cabale will likely have to be atleast 150 feet, do you think it will degrade the signal from this closer station as some people have said that for close stations a preamp will make the signal worse. If so what can be done?
post #1516 of 16086
Quote:


Originally posted by VMsat
Thanks. I have another question. My parents like in the country and have a 35 foot antenna mast which is mounted in the ground about 50 feet from their house. The main tv is another 100 feet or more to the other side of the house. I think the CM 4228 is a good choice for UHF since some of the stations are atleast 50 miles or so away. However, one of the stations is only about 5 miles away from their house. My question is if a CM 7777 preamp is used, as the cabale will likely have to be atleast 150 feet, do you think it will degrade the signal from this closer station as some people have said that for close stations a preamp will make the signal worse. If so what can be done?

If they are truly "in the country" then this station is likely a low-power station, in which case it isn't a problem. If it's a full-power station, it may overload the preamp in which case you'll need to notch it out or attenuate it. Fixed filters of this type can be had at http://www.tinlee.com/
Blonder Tongue makes adjustable notch filters (very expensive) as does Winegard (for uhf only). The adjustable filters require time and effort as well as at least an analog TV without a mute circuit.

If you use a notch filter, you will most likely attenuate at least a channel above and below as well, depending on the slope of the filter.
post #1517 of 16086
Where do I go to find out if this is a low power station. I just went to antennaweb.org and it does not show the power.
post #1518 of 16086
Okay i found it on tvradioworld, it is 12.9 kW. Is this considered low power?
post #1519 of 16086
How accurate, generally, are AntennaWeb's projections. I know they say they're somewhat conservative, but for me they say I can receive UHF transmissions from 120 miles away with a Violet Antenna (LD with Preamp). I read that to basically say CM 4228 + CM 7777. I can receive my local stations fine all of them. This is more basically a curiousity to me, that "conservatively" I could get 5 stations from 120 Miles away and 1 station in Reno from 140 Miles away (all Violet, not Pink). (They're analogs, but still I'm curious as it might also put me outside of some blackout areas...not that I'd ever consider that as a reason to go outside my DMA). Right now I'm have with a CM 4221 no Preamp or Amp, and do just fine for locals.
post #1520 of 16086
Quote:


Originally posted by VMsat
Okay i found it on tvradioworld, it is 12.9 kW. Is this considered low power?

Depends on whether that's lo-VHF (channels 2-6), hi-VHF (channels 7-13) or UHF.

If it's UHF, it's low power. If it's lo-VHF, that's pretty hot. Hi-VHF is in between.
post #1521 of 16086
It's channel 4 so I might need an attenuator i guess if i use a preamp. I live in west texas in the middle of almost nowhere and none of the so called local stations i get, ( although they are from a larger city about 50 miled away Midland /Odessa area) broadcast in HD although they are in digital. Lubbock, a larger city 100 miles to the north on the other hand has three stations in HD, channel 9-1 (NBC), 5-1 (PBS), and 35-1( another network not sure if CBS or ABC). Right now with my sensar II antenna mounted on a twenty foot mast on the roof with rotor, I get some of the Lubbock stations some of the time. I never get any of the Midland/Odessa stations which is only 50 miles away, probably because of a hill between my house and that city. The terrain between my house and lubbock (100 miles away) is 100% completely flat. Probably the flattest 100 mile strtch in the whole country. Now when I get my new CM 4228 and CM 7777 preamp I'm hoping to get these HD stations out of Lubbock. The problem is the 4228 is UHF and channel 7-1 and 5-1 are not UHF stations, but I understand that that antenna is also good with higher VHF stations. What do you think, might I be able to bring in these stations?
post #1522 of 16086
Quote:


Originally posted by VMsat
It's channel 4 so I might need an attenuator i guess if i use a preamp. I live in west texas in the middle of almost nowhere and none of the so called local stations i get, ( although they are from a larger city about 50 miled away Midland /Odessa area) broadcast in HD although they are in digital. Lubbock, a larger city 100 miles to the north on the other hand has three stations in HD, channel 9-1 (NBC), 5-1 (PBS), and 35-1( another network not sure if CBS or ABC). Right now with my sensar II antenna mounted on a twenty foot mast on the roof with rotor, I get some of the Lubbock stations some of the time. I never get any of the Midland/Odessa stations which is only 50 miles away, probably because of a hill between my house and that city. The terrain between my house and lubbock (100 miles away) is 100% completely flat. Probably the flattest 100 mile strtch in the whole country. Now when I get my new CM 4228 and CM 7777 preamp I'm hoping to get these HD stations out of Lubbock. The problem is the 4228 is UHF and channel 7-1 and 5-1 are not UHF stations, but I understand that that antenna is also good with higher VHF stations. What do you think, might I be able to bring in these stations?

As far as I can tell, in the Midland/Odessa as well as Lubbock area, the only VHF digital you have is on ch. 9 from Lubbock. The channel 4 you are referring to is an analog NBC from Big Springs. You should do fine with the 7777 and the CM 4228. Hook to the "combined" input and be sure the internal switches are set to "combined" and the FM trap "in". The 4228 should do a very nice job of attenuating channel 4 as it's gain is minimal there. It should do pretty well for channel 9 but if you need more add an Antennacraft Y10 7-13 or equivalent high band antenna which still will not likely have enough channel 4 gain to overload the preamp.
post #1523 of 16086
Thanks for the information, I will try the 4228 with the 7777 first and then upgrade if needed.
post #1524 of 16086
Many thanks to all who replied to my post about ch.13 cci from a couple days ago. The information was very helpful and much appreciated!

I'm leaning toward trying one PSP.1922 initially and then perhaps two horizontally stacked.

I've been waiting for the ch.13 analog in question (WOWK-DT47, Huntington,WV.) to improve the quality of their digital signal. I can receive their digital, but to say they're not passing HD would be a gross understatement, as all the folks in the Charleston,WV section can attest. I'd rather watch a semi-noisey analog!

Thanks again!
post #1525 of 16086
I hate doing this, but I'm driving myself nuts trying to get a local CBS station and have had zero luck. I'm trying to pick up WWMT, a CBS out of Kalamazoo/Grand Rapids. I'm 31 miles southeast of the antenna. I'm also in a southeast facing apartment meaning I have several walls to go through. I am on the 2nd floor however. I've tried a folded dipole with little luck. The station is on the frequency assignment 2, but is channel 3.1. Anyway, I went to Menards, a lowe's/home depot style store and bought a Magnavox outdoor antenna (I think they call it yagi-style). Granted it was only 30 bucks and probably about 60" in length, I was still able to pull in somewhat decent analog signals without too much trouble. But when I try to pull in the digital signal, I max out at 41%. That's the same I maxed out at with the folded dipole. It's the same across several other VHF channels, where I can get a somewhat decent analog signal, but max out at 41% when I try to pull in the digital signal. Am I doing anything wrong? Do I need a pre-amp or something (not even sure what a pre-amp does)? Would I be better off contacting the stations engineer to see if he knows of any reason I'd be having so much trouble?
post #1526 of 16086
Quote:


Originally posted by SteveMSU
I hate doing this, but I'm driving myself nuts trying to get a local CBS station and have had zero luck. [...]I was still able to pull in somewhat decent analog signals without too much trouble. But when I try to pull in the digital signal, I max out at 41%. That's the same I maxed out at with the folded dipole.

If you haven't tried it yet, this page has some good information on building your own specific frequency antenna: http://www.wfu.edu/~matthews/misc/dipole.html If you add his recommended improvements at the bottom of the page, you should have a far better antenna than the VHF/UHF combo you picked up at Menard's. You might find that a stack of two of these home-built antennas is necessary for best results.

Digital VHF signals can be tricky because most areas of the country were already "saturated" with analog signals. The FCC has tried to squeeze some digital stations into the mix, but the fact is that co-channel (meaning the same channel) interference is going to be a problem for most people outside of the Grade A contours. Given the difficulty of your local environment, you've got at least two strikes against you at the get-go.

You may not be able to get better reception no matter what you do. I doubt signal strength is your real problem. You probably have more interference and ghosting than weak signal problems. (Weak signals look like "snow" on analog.) Thus a preamplifier is not going to help. All I can suggest beyond the antenna above is to use the latest tuners, with the advanced chipsets. Good luck.
post #1527 of 16086
I need a antenna that will go at least 100 miles. for 250.00$ or less. Any Suggestions? ZIP 32456
post #1528 of 16086
Quote:


Originally posted by Audioman1
I need a antenna that will go at least 100 miles. for 250.00$ or less. Any Suggestions?

Depending where you are it can be done. If you are low in between mountains forget it. If your relatively flat like in Texas may not be a problem. Give us a zip and see if one of us can help you.
post #1529 of 16086
Quote:


Originally posted by j_buckingham80
How accurate, generally, are AntennaWeb's projections. I know they say they're somewhat conservative, but for me they say I can receive UHF transmissions from 120 miles away with a Violet Antenna (LD with Preamp). I read that to basically say CM 4228 + CM 7777. I can receive my local stations fine all of them. This is more basically a curiousity to me, that "conservatively" I could get 5 stations from 120 Miles away and 1 station in Reno from 140 Miles away (all Violet, not Pink). (They're analogs, but still I'm curious as it might also put me outside of some blackout areas...not that I'd ever consider that as a reason to go outside my DMA). Right now I'm have with a CM 4221 no Preamp or Amp, and do just fine for locals.

Antennaweb is usually accurate with analogs but very conservative with digital. Have you tried getting a signal from that direction with the 4221?
If you do get a signal then the 4228 with the 7777 will probably bring them in. 140 miles is a haul for any antenna. The natural curve of the earth is the killer. I can get ground reception late night digital out to about 200 miles but not reliable enough to watch. I do have mountains and other geographical problems here not to mention 2 digital channel 7's and soon to be a third.

In my case here antennaweb says I should get 2 digitals with a violet antenna and booster. I get reliable 14 digitals with a 7777 or 12 without any amp. If they say you can get digital reception from that far I'd bet money you can.
post #1530 of 16086
Quote:


Originally posted by jimc705
Depending where you are it can be done. If you are low in between mountains forget it. If your relatively flat like in Texas may not be a problem. Give us a zip and see if one of us can help you.

I need a antenna that will go at least 100 miles. for 250.00$ or less. Any Suggestions? ZIP 32456
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