Thread: Reception
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Old 23-Sep-2015, 1:49 PM   #7
rabbit73
Retired A/V Tech
 
Join Date: Aug 2012
Location: S.E. VA
Posts: 2,747
KOMO ABC, real channel 38, virtual channel 4.1, NM 1.1 dB
KING NBC, real channel 48, virtual channel 5.1, NM -6.9 dB
KIRO CBS, real channel 39, virtual channel 7.1, NM -7.4 dB

Do I see solar panels on your roof? See attachment 5.

Inverters can create interference for TV signals. Modified sine wave inverters (should be called modified square wave inverters) create more EMI than sine wave inverters. The interference can be conducted, radiated, or both. Some users need to move the antenna away from the inverter and run the TV on a small sine wave inverter like the Exeltech XP125. (I read Home Power magazine.)

Terrain profiles for KING:





And here is the coverage map; not much signal at the fringe:



The results for KOMO and KIRO are similar.

In order to keep the strong VHF and FM signals out of the preamp and tuner, I suggest you try this:
Code:
 91XG > UVSJ > AP4800 > 
                       \
                       AD EU385 > coax > power inserter > TV
                       /
YA1713 Yagi > FM trap >
The second UVSJ between the 91XG and the preamp attenuates the FM and VHF signals, but allows the UHF signals to pass through. FMFOOL report in attachment 4.
http://www.mcmelectronics.com/produc...-FM-88-/33-341
https://www.antennasdirect.com/store...on_filter.html

If KTBW is too strong for the preamp, switch to a preamp that resists overload better, as ADTech and Tower Guy suggested. ADTech did some preamp tests in a strong signal area that show the Winegard Chromstar UHF preamp overloads easily which harms the weak signals:

A Building Can Ruin Your Whole Day!
http://forum.tvfool.com/showthread.php?p=50328





It looks like with the preamp about half the signals were damaged beyond recovery. The weakest signals are the first to go when you have overload.
Attached Images
File Type: jpg fusionteckHDFp2aKING.JPG (61.7 KB, 1292 views)
File Type: jpg fusionteckHDFp2bKING.JPG (118.2 KB, 1281 views)
File Type: jpg fusionteckHDFc2KING.JPG (93.9 KB, 1361 views)
File Type: jpg fusionteckHDF FM.JPG (108.3 KB, 554 views)
File Type: jpg fusionteckHDFaerial.JPG (105.3 KB, 560 views)
File Type: png ADTech parkig lot1 (2).png (193.2 KB, 1492 views)
File Type: png ADTech parking lot2 (2).png (203.4 KB, 1449 views)
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Last edited by rabbit73; 23-Sep-2015 at 2:28 PM.
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