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Old 16-Aug-2017, 1:09 AM   #2
rabbit73
Retired A/V Tech
 
Join Date: Aug 2012
Location: S.E. VA
Posts: 2,748
Welcome to the forum, Tvaddict17



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Currently, I have the 7698 mounted in the attic, pointed towards Bremerton and Seattle.
Your channels are pretty weak for an attic antenna. Signal loss in an attic is difficult to predict.



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Early on, I picked up a Winegard LNA-200, (which made things worse).
That's odd; it should have helped.

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KING 5 NBC real ch.48 all the time....KOMO 4 real ch. 38 ABC most of the time
It is difficult to receive signals with a NM of less than -10 dB. If you are able to receive signals with a NM less than -10 dB, you have an excellent antenna system, or the tvfool report is wrong (often possible with weak signals), or they have been enhanced by Tropospheric Propagation, which is common at this time of year.



Interpreting Noise Margin in the TV Fool Report

http://www.aa6g.org/DTV/Reception/tvfool_nm.html


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KIRO 7 CBS real ch.39 almost never.
That one is also too weak.
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I know there is a KIRO 7 Transmitter only 4 miles from me, but a different direction.
Yes, that is KIRO real channel 28. There are four KIRO transmitters that have different real channel numbers, but the same virtual channel number (7.1) that is displayed on the TV. If you are going to use the virtual channel number, please use the decimal form to avoid confusion.
http://www.rabbitears.info/market.ph...&callsign=KIRO

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Is there a way to get KOMO 4 (real ch.38)
That is too weak for reliable reception, especially with an attic antenna.
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and the KIRO station near me better?
That one, KIRO real channel 28, should be easy. The antenna must be aimed at 285 degrees magnetic. The 7698 antenna is very directional.

There are often multipath reflections in an attic that make it impossible for the tuner to decode the signal, even if it is strong enough. Have you tried different locations in the attic?

Are there any trees in the signal path? Trees block TV signals.
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Would the DB8e and a separate VHF antenna work better for me.
Maybe; the DB8E has good gain at the low end of the UHF band where many channels are moving to after repack (14-36).



What VHF channels are you interested in?

It is the real channel number that determines what antenna is needed.

VHF-Low, real channels 2-6
VHF-High, real channels 7-13
UHF, real channels 14-51 (soon to be 14-36)

The virtual channel number (like 5.1) is a holdover from the analog TV days to maintain the identity of the station, and is what the TV displays.
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File Type: jpg TVFOOL Signal Analysis_1.jpg (98.8 KB, 719 views)
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Last edited by rabbit73; 12-Sep-2017 at 5:32 PM.
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