Preamp Issues (1 Viewer)

Neutron

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Starting a new thread on this. I installed my preamp yesterday and it has killed the signals I got without it.

I dedicated a coax from our antenna to the OTA module on our 722k. Before I had it all going through our DISH equipment outside diplexed on to the DISH cable coming inside.

Our ABC tower is the closest and antenna alone it will come in at 100 at night. With the preamp it drops to 75-85 depending on what I have the gain set to. CBS NBC and FOX are all at 65 to 70 at night. With the preamp I get nothing.

During the day without the preamp I can only get ABC.

I'm really not sure what the deal is. It makes no sense to me why the signal drops with the preamp. The antenna is about 15 feet off the ground.

Attached is my original TVFool report. The antenna is an Antennacraft HBU33 and the preamp is an Antennacraft 10G212.

There is less than 75 feet of coax line total.
 

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sergei

SatelliteGuys Pro
Aug 29, 2007
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iowa
First thing try testing it by just using a separate TV and bypassing the 722 input and everything else and see how the antenna and preamp are working by themselves.
 

Tower Guy

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Nov 1, 2005
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During the day without the preamp I can only get ABC.

You have two possible issues.

1. Your ABC station is strong enough to overload many preamps.
2. The satellite combainer may or may not pass DC power to the preamp.

The solution to the first problem is to use a UHF only preamp. The Winegard AP 4700 is a good choice.
The second problem would take an ohmmeter to diagnose, or you may simply use a dedicated RG-6 for the line between the preamp and the diplexor.
 

boba

SatelliteGuys Master
Dec 12, 2003
11,351
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Dorchester, TX.
Jason you probably won't like my answer but here goes.

KETK NBC is 61.4 miles away with a 2 edge designation
KFXK FOX is 51.6 miles away also 2 edge
KYTX CBS is 73.1 miles away also 2 edge
The antennacraft HBU33 is rated for 60Mi. UHF in good reception conditions 2 edge means you have some interference between you and the broadcasters. Adding an amplifier does no good because the amplifier needs a signal to amplify. My guess is you don't have a usable signal from those 3 networks. ABC at 28 miles has too much signal going into the amplifier so the amp overdrives the signal.

You probably need a high gain UHF antenna such as a Channel Master 8 bay bowtie which also may receive your VHF ABC with enough signal to work. An amplifier is not a cure all in"IT" it might be close to GIGO, if you amplify garbage it is still garbage. You may also need more heigth 15 feet may not be enough. Post your zip code so we can play on TV Fool.
 

Neutron

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75494

I can get in all 4 stations at night. ABC is between 90-100 at night, and can be viewed during the day. The other 3 I can view at night with only slight pixilation every now and then with CBS in the 60s at night.
 

Neutron

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Would the Antennacraft HBU55 be better? I'm thinking of exchanging the preamp out and paying the difference and just getting the bigger antenna.
 

Bob2011

SatelliteGuys Pro
Jan 5, 2011
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Hudson Valley NY
Well if the ABC station was overloading the amp or receiver as others have stated then it could easily be solved by moving the antenna left or right of the tower. I doubt this is the issue but worth a try. Like I mentioned in the other thread, signal noise is more likely a cause. Either it is coming from the preamp itself or entering your cable from other electronics on the same power circuit. The preamp is not the best out there noise wise at 4 db but far from the worst.

Another option here is to use a separate UHF antenna for these distant stations. If you were able to install an antenna on your own then I'm sure you have the ability to build your own 4 bay antenna to experiment with. I have recommended the mclapp M4 designs in another thread as they are easy to build and work well even without the reflector. Here is a link with photos and design diagrams.

DIY TV Antennas 4 bays, 2 bays, Kits and more

You would still use the HBU33 for the ABC station but use a combiner to block the UHF from that antenna and instead get it from the 4 bay.
 

Neutron

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Are there any antennas out there that can pull in UHF from more than 60 miles?
 

No Static At All

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Aug 18, 2008
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A dedicated UHF antenna will provide a more reliable signal than any combo antenna. I have used the 91XG at a few different locations & have always been pleased with the results. I reliably receive 2 stations over 60 miles away here with the 91XG through 75 feet of coax with no amplifier. WHAG & WWPB.
 

Teehar

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Sep 29, 2010
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I could be wrong but I still think you got a bad preamp.Your signal strength shouldn't get weaker when connecting the preamp.
 

Bob2011

SatelliteGuys Pro
Jan 5, 2011
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Hudson Valley NY
Are there any antennas out there that can pull in UHF from more than 60 miles?

Your antenna can get stations from 150 miles if it is high enough to be line of site. You really can't pick an antenna based on advertised mileage numbers. When you're not LOS then it all comes down to what kind of obstructions there are between you and the transmitter. The TV Fool numbers don't take into account trees and buildings near your antenna. So if you have a large building that the signal has to bend over to reach your antenna then you will need to make up several dbs of loss with a larger antenna. When you have diffraction like this there can be hot spots at different points on your roof so moving the antenna can often make a big difference.

I get the feeling based on the zip code that you gave us you probably live in town and may have obstructions like this. Your consistent night time improvement when the stronger signal refracts downward shows you're right on that edge of good reception. The amp should have overcome the line loss to make those stations near perfect at night.
 

mike123abc

Too many cables
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Sep 25, 2003
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You might have to get an UHF only amplifier. Your ABC is on 7, the others are all UHF. I had a similar situation before the final DTV conversion. I had to use a band separator to separate VHF-Lo, VHF-Hi and UHF. I had to use an attenuator on VHF-Lo (channel 3 was overloading everything being less than 5 miles from the tower), a small amp on VHF-Hi, and a big amp on UHF. Now after the conversion I just use a UHF amp, the one remaining channel on VHF is far enough away (about 30 miles), but strong enough that it can come in without having to worry about amplification.
 

boba

SatelliteGuys Master
Dec 12, 2003
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Dorchester, TX.
Are there any antennas out there that can pull in UHF from more than 60 miles?
My answer to your question is Channel Master CM4228 I've used it in Gunter to receive Dallas stations at about 62-63 miles without amplification.

Using the Winnsboro ZIP code 75494 I get different results from what you posted so I am guessing you used your actual address. With 75494 your ch.7 degrades to a 2 edge station so you have a "good" location for reception. Taking your antenna heigth up to 50 FEET your ABC and NBC improve to LOS line of sight and others improve to 1 edge. My conclusions are you need a better UHF antenna and more heigth. Seeing your actual location may have more elevation than the center of Winnsboro you may not need 50' but you do need more than 15'. Go to TV Fool and play with the antenna heigth at your actual address to see how low you can actually mount the antenna. With additional elevation wind resistance becomes more important so the 8 bay bowtie is favored and the possibility of also getting ABC's VHF signal is my reason for the CM4228.
 

Neutron

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We are south of the city center. We do have trees as East Texas is known for its piney woods, but there are no trees directly in front of the antenna and the closest obstruction per say would be the power pole at the edge of the property, which is about 25-30 feet away from our roof line.

Would a different preamp be a solution? Summit Source is going to give me store credit once I return this one. So I can either keep the HBU33 and use a different preamp, or use a different antenna alltogether.

Not sure if this is prevalent or not, but I can't get the antenna dead level on the peak of my roofline due to the mast I'm using. I'm using an old satellite dish mast and we had to really make it work to mount the antenna to the mast. Because of the lower boom on the antenna we couldn't get it exactly level with the ground, so it tilts up a little bit with the "V" of the boom pointing slightly to the sky but it is toward the towers. I will take a picture of this when I get home. I would say the angle is no more than 10-20 degrees.

There's no way at all I can raise this thing to 50 feet or anywhere close to it. We live in town and even though the town doesn't have a lot of regulations regarding residences, I'm sure I would get flagged if I raised it that high.
 

boba

SatelliteGuys Master
Dec 12, 2003
11,351
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Dorchester, TX.
We are south of the city center. We do have trees as East Texas is known for its piney woods, but there are no trees directly in front of the antenna and the closest obstruction per say would be the power pole at the edge of the property, which is about 25-30 feet away from our roof line.

Would a different preamp be a solution? Summit Source is going to give me store credit once I return this one. So I can either keep the HBU33 and use a different preamp, or use a different antenna alltogether.

Not sure if this is prevalent or not, but I can't get the antenna dead level on the peak of my roofline due to the mast I'm using. I'm using an old satellite dish mast and we had to really make it work to mount the antenna to the mast. Because of the lower boom on the antenna we couldn't get it exactly level with the ground, so it tilts up a little bit with the "V" of the boom pointing slightly to the sky but it is toward the towers. I will take a picture of this when I get home. I would say the angle is no more than 10-20 degrees.

There's no way at all I can raise this thing to 50 feet or anywhere close to it. We live in town and even though the town doesn't have a lot of regulations regarding residences, I'm sure I would get flagged if I raised it that high.
For an amplifier to improve anything it has to have a signal to improve. If you don't have daytime reception that is due to a poor signal. If you amplify a poor signal all you can get is an amplified poor signal, the only way to improve the signal is more elevation or a better antenna. My suggestion was to go to TV Fool and play with the elevation at your real location look at the signal strength and path columns to see if there are improvements. It might take only a 10 foot increase in mast length to improve your signal, in most towns that wouldn't raise an eyebrow. A satellite mast in most cases isn't enough elevation for country reception

You have 60 miles between you and the broadcast towers a hilltop 20 miles from you could weaken the signal you receive it isn't just the power pole 30 feet away that you need to worry about for interference. Keep the preamp until you put up an antenna that gets a usable signal, you may still want to amplify your final system.
 
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Mr Tony

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Nov 17, 2003
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The HBU33 is a little "Weaker" in my opinion on UHF. I have one of these and get my stations 30 miles away just fine but I think anything more than 40 miles a bigger UHF portion of an antenna would be better

The VHF portion I can get a station 72 miles away. BUt my YA-1713 blows it out of the water signal wise ;)
 

Teehar

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Sep 29, 2010
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His booster (Antennacraft 10G212) is uhf/vhf.I have the same amp and a 4 bay philips uhf antenna and pull in stations from Charlotte,Greensboro,Winston Salem.Some of them are 150 miles from me as the crow flies.Without the amp signal levels drop to un-lockable strength.With it I get mid 70's low 60's on average.
 

Neutron

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It's getting a signal for all 4 stations, it's just that I don't know what it is when it drops out as the 722k will report a weak signal as a 0.
 

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