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jao988
13-Mar-2011, 1:53 PM
http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3d59791b7722e943

I've been using the same antenna setup since the DTV transition with generally good reception for our local TV stations. Sometimes a heavy windy storm will blow the antenna off aim.

All of a sudden I'm not getting anything no matter how the antenna is aimed. I know the usual direction at this point and I'm getting signal strengths in the 0-40 range (based on the Tivo signal strength meter). Normally I get strengths in the 75-99 range.

Setup includes:

Roof mounted (ranch style house - 15' mast) UHF/VHF antenna from radio shack (looks similar to a channel master cm3016)

Antenna mounted powered pre-amp (don't remember model, but purchased online based on recommendations from these forums)

Splitter to 3 different TV's , one has about a 30' run, the others 75'-100'+ runs.

Nothing has changed in our setup when the signal dropped. I thought the wind had blown the antenna off of the correct location.

Any ideas?

No static at all
13-Mar-2011, 3:41 PM
Sounds like the preamp is defective. The mast mounted part of the system must be bypassed to confirm this. I would suggest replacing the pre-amp with a Channel Master distribution amp if this turns out to be the case.

I'm guessing you are using the Winegard HDP-269 which is prone to failure from static build-up on improperly grounded antenna systems. (Happened to me in less than 2 weeks & read of others having issues with the same model)

John Candle
13-Mar-2011, 10:13 PM
The television transmissions are strong at magnetic compass 175. . An amplifier should not be needed for 1 , 2 , or 3 tv's.

jao988
14-Mar-2011, 1:51 AM
I bypassed the Preamp and did receive some acceptable signals, but not as many as with the Preamp working, so it does look like the preamp is bad. I don't think it is even two years old...I was using a CM7778. Do you have a suggestion for another one?

As for the other comment regarding reception and whether I need a preamp, my antenna is aimed directly through some 60' plus oak trees in the next yard and I don't really think that my antenna is as high as it should be.

The only other problem I have had is that it seems I lose good signal strength as soon as a high wind storm comes through and rotates the antenna as little as 2-5 degrees.

Is there another type of antenna that would suit my needs and still allow me to recieve the one low VHF (6) channel in my area?

Thanks for all of the advice.

No static at all
14-Mar-2011, 2:13 AM
I recommend the Winegard 7084. It may even be enough antenna to power all 3 TV's without additional amplification. A smaller antenna may work, but not sure how much affect the trees are having on the signal. I like going a size or 2 larger to ensure better reliability during adverse weather conditions.

GroundUrMast
14-Mar-2011, 2:35 AM
I recommend the Winegard 7084. It may even be enough antenna to power all 3 TV's without additional amplification. A smaller antenna may work, but not sure how much affect the trees are having on the signal. I like going a size or 2 larger to ensure better reliability during adverse weather conditions.

Agreed.

I would be curious how things perform if a new or known good coax from the antenna to a single set were installed as a test.

Something does not add up here. The signal levels shown on the TVF report should be in excess of what is needed to overload the CM7778. (Or somebody tell me I'm doing the math wrong.) That suggests that there has been a long standing problem with the antenna, matching transformer, cables or connectors. Such a problem may have been masked by the gain of an amplifier that should not be needed.

An un-amplified antenna with a few dB of forward gain should be capable of driving a passive 4-way split.

Time to critically look at each component and connection...

John Candle
14-Mar-2011, 10:45 PM
I agree with GUM and NSAL. A Known To Be Good Antenna , A Known To Be Good Matching Transformer To Connect The Antenna To The Known To Be Good Single Run Of Coax that Goes Direct To One Know To Be Good Tv. With No Type Or Kind Of Amplifier.