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Old 5-Dec-2016, 8:10 PM   #7
rabbit73
Retired A/V Tech
 
Join Date: Aug 2012
Location: S.E. VA
Posts: 2,753
Thank you for the new report. Your TV and FM signals are still very strong.
FM
http://www.fmfool.com/modeling/tmp/3...3/Radar-FM.png

In addition to following the advice by ADTech, I suggest you try inserting an attenuator in the coax line between the antenna and the tuner to see if overload is a problem. Also try inserting an FM filter to attenuate your local FM signals.

A splitter can be used as an attenuator; 3 dB for a 2-way splitter, 7 dB for a 4-way splitter. There is also a variable attenuator available:
https://www.antennasdirect.com/store...ttenuator.html



The ATT-1 knob has 3-3/4 turns, so I put a mark on the knob with an ultra fine point Sharpie to count the turns. Clockwise rotation increases the signal; minimum attenuation at full clockwise rotation. When I use mine to make tuner sensitivity tests, I start there, and rotate the knob counterclockwise to increase the attenuation for the test.
http://www.avsforum.com/forum/186-co...l#post48473881

You can try this FM filter

https://www.antennasdirect.com/store...on_filter.html

or use a HLSJ as an FM filter, which blocks everything below CH7, including the FM band.
http://www.solidsignal.com/pview.asp?p=zhlsj

WITRELESS ENGINEER has a good point about possible cell tower interference.
Attached Images
File Type: jpg CM7003ATT-1s.jpg (73.5 KB, 1679 views)
File Type: jpg HLSJ as FM Trap.jpg (71.7 KB, 1211 views)
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Last edited by rabbit73; 5-Dec-2016 at 8:30 PM.
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