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Old 4-Mar-2018, 7:59 PM   #7
rabbit73
Retired A/V Tech
 
Join Date: Aug 2012
Location: S.E. VA
Posts: 2,544
Thank you for making the test and for the TVFool report. Your report shows WTVW with a signal power of -2.2 dBm highlighted in red, which is an overload warning. A preamp is contraindicated unless you insert a custom filter before the preamp to attenuate real channel 28.

I had been wondering about the Televes preamp that adjust the gain. It might work at a location with all weak signals or all strong signals, but with a mixture of weak and strong signals, it is the wrong choice. Your location was ideal for the test; it showed the weakness of the concept. We appreciate the report of your experience; it will help us when giving advice to other posters.

The best clue you gave is when you said you had to rotate the antenna off-azimuth. That reminded me of a case in Las Vegas. The poster was using one of those cheap "150-mile" antennas that also have a preamp with waaaay too much gain. He also had to aim off-azimuth to prevent overload. The only reason to use a preamp with that much gain is when you have a very long coax line after the preamp to compensate for the signal loss from coax attenuation.
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Last edited by rabbit73; 4-Mar-2018 at 8:27 PM.
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