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Neutron
02-18-2012, 01:20 PM
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.

sergei
02-18-2012, 02:28 PM
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
02-21-2012, 09:41 AM
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
02-21-2012, 01:19 PM
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
02-21-2012, 01:48 PM
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
02-21-2012, 08:17 PM
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
02-21-2012, 09:26 PM
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 (http://m4antenna.eastmasonvilleweather.com/index.html)

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
02-22-2012, 08:03 PM
Are there any antennas out there that can pull in UHF from more than 60 miles?

No Static At All
02-22-2012, 09:36 PM
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 (http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3da36213047389ee%26t%3dALLTV%26n%3d35) & WWPB (http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3da36213047389ee%26t%3dALLTV%26n%3d40).

Teehar
02-22-2012, 10:20 PM
I could be wrong but I still think you got a bad preamp.Your signal strength shouldn't get weaker when connecting the preamp.

Reigster at SatelliteGuys