radiosh@ck 15-2507 amp boosts UHF - kills VHF

[H454]

Hi, first time post here.
Have problems with HDTV/DTV signals.

I have A large VHF/UHF antenna in my attic(two stories), live in Lakeville, MN (zip 55044), about 30/maybe 40 miles from transmitters in shore view, MN.

Two years ago, I put a RS 15-2507 amp on the antenna and most of the Digital channels work great - very few problems.

Now after June 12th, channels 9 and 11 WENT BACK to physical channel 9 and 11 (used to be broadcast in UHF).

Here's the problem, with the amp, NO VHF (9,11) - great UHF.
NO amp, great VHF, not so hot UHF ( no 41,45, some channel intermittent.)

Is their Some to only amplify UHF?
Also, I looking to solve this as cheap as possible.

Any Help is Greatly appreciated.
thanks

Channels
Analog CH | Call Letters | Temp. CH | Perm. CH | Analog Power | Digital Power | Trans. city
2 KTCA PBS 34 34 100KW 924KW Shoreview East
4 WCCO CBS 32 32 100KW 1000KW Shoreview West
5 KSTP ABC 50 35 100KW 1000KW Shoreview West
9 KMSP FOX 26 9 316KW 691KW Shoreview East
11 KARE NBC 35 11 316KW 774KW Shoreview West
17 KTCI PBS 16 26 141KW 50KW Shoreview East
23 WUCW CW 22 22 4570KW 1000KW Shoreview West
29 WFTC UPN 21 29 5000KW 1000KW Shoreview East
41 KPXM ION 40 40 2770KW 1000KW Big Lake MN
45 KSTC Ind 44 45 5000KW 82KW Shoreview West

 

[No Static At All]

Do you have the FM trap turned on?

 

[Mr Tony]

welcome

dang hoss I'm in Shakopee and use just a Radio Shack U-120 and get everything fine with no amp. Sure I lost 8 points on 9 (was 100 now 92) and maybe 3 or 4 on 11 on the HDTV but the rest come in great. Even get low powered 25 (digital)...dont get 41 but that is due to very leafy trees in the way

That amplifier is overkill in the metro area. (use to work at Radio Shack)...We use one of those on Mille Lacs to get the stuff from Brainerd and Channel 12 (CBS) in Walker

 

[H454]

Fm trap is always on - the has "in" or "out" - Note tried channel rescans with three tvs on both settings.
I think most of the problem is the amp is over driving the VHF.
Also Lakeville is mailing address, I live in Eureka township (240th st).
I was thinking of trying something like this:

Winegard AP 4700 Chromstar 2000 Series UHF Pre Amplifier (AP-4700)

 

[CowboyDren]

I'd just get a VHF only antenna and a UVSJ signal combiner. Run the new antenna into the UVSJ, then your current antenna with amplifier into the other side of the UVSJ, and you should be fine.

 

[Mr Tony]

it does sound like the amp is overdriving the VHF....I have a UHF amp somewhere around the house...wonder if it just passes VHF just fine??

 

[H454]

That why I was looking at Winegard AP 4700 , Because it amps UHF only and gain is like low/mid 20s. I think between 20 & 30 would perfect, (have four tv on this antenna and long cable runs).

Had one tv hooked directly to antenna and rest on the amp. Thats How I figured out it was the amp.

 

[H454]

Also, I want to get a new antenna or remount it, because I know theirs simple solution I/we haven't thought of.

 

[CowboyDren]

What does the UHF section of your current antenna look like? Is it all pretty standard YAGI/Fishbone fare? Is there a chance your UHF elements are simply broken?

 

[H454]

Highly doubt its broken - that why its mount in the attic.
Antenna looks almost exactly like this:

Channel Master CM 3671 Deepest Fringe Crossfire Series Antenna (CM3671)
Channel Master CM 3671 Deepest Fringe Crossfire Series Antenna (CM3671) | CM3671 [Channel Master]

 

[CowboyDren]

Right; in-attic installations don't break often, but what about corrosion at the feed points? I'm just spit-balling, here...

 

[H454]

Post from earlier was suppose to say I DON"T want to get a new antenna or remount it.

 

[Tower Guy]

I was thinking of trying something like this:

Winegard AP 4700 Chromstar 2000 Series UHF Pre Amplifier (AP-4700)

I have one. It will do exactly what you need it to do.