Inconsistent performance with new attic install

[crichman]

We're just inside Washington DC's Beltway in 20817, and used a roof-mounted antenna for years. Recently we removed it and went with an Antennas Direct DB4 and Wineguard AP-8700 mounted in the attic. The (relatively long) coax goes to the power injector and then to a 3-way splitter. The antenna is pointed at exactly the 161 degrees (magnetic) indicated by AntennaWeb for our location.

We're getting good signal strength on all channels, but with periodic dropouts where the s/n and overall signal indicator on the tv indicate a momentary loss of signal. This seems worst on channels 4 and 5 (rf 36 and 48). It really isn't acceptable.

How can I go about troubleshooting this? I'd really prefer to avoid mounting the antenna on the roof, especially because the periodic dropouts make me suspect electronics more than metal.

Thanks!

Charlie

[winegard]

Good afternoon Charlie,


Run a coax cable directly from your antenna to one TV set with out the AP-8700 preamplifier or splitter in the line to see what kind of TV reception you have. Next add the AP-8700 and run a single cable directly to one TV set and monitor you picture. Now add your splitter and monitor the pictures. You are only 4-5 miles from your TV stations and you are using an AP-8700 preamplifier which has 19dB of gain (multiplies your signal 8.9 times) on the UHF band.

At this close distance it is possible that you have over amplified these channels when the signal fluctuates and made them too strong for the TV tuner to handle. Try installing a -3dB or -6dB or both screwed together (9.0dB) attenuator pad ahead of your splitter to reduce the signal strength going to your TV sets to see if that solves your problem.

[crichman]

Thanks. Will do (though I'm a tad skeptical -- I added the preamp when the attic-mounted antenna wasn't sufficient on its own.) It's also possible that there is an interference issue from local radio towers not far off.

The funny thing is seeing good signal strength indication on the TV that suddenly drops out. It's not as if it is fluctuating wildly and sometimes hitting a low limit -- it's as if it is completely steady except for moments when it's gone.

Charlie