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Old 9-Jun-2016, 12:40 AM   #16
Retired A/V Tech
Join Date: Aug 2012
Location: S.E. VA
Posts: 2,738
Thanks for the update and keeping it on the same thread.

I think you are doing very well with your attic antenna, and a preamp does help.
Is the dipole a great idea?
A folded dipole for Ch 6 is a good idea, but I'm not sure it would be worth the trouble because your CM3016 covers VHF-Low. CM states the VHF gain as 7.9 dB, but they do not say what it is for Ch 6.

The next step up in a DIY antenna for Ch 6 would be a 3 element beam using aluminum tubing or wire (use good insulators at the ends of the wires).

I designed the antenna for mpcary at AVS who was also trying to get WPVI, but I don't know if he ever got it.

I did a new tvfool report based on an estimate of your location because WPVI has increased their power since your old report. Other people have also had trouble with WPVI because the noise level from electrical interference on VHF-Low is higher than on VHF-high.

You can see that WPVI is now at the top of the list but it is still a weak signal. If you do have a high noise level you might be able to track it down with an AM portable radio for the broadcast band tuned to a vacant frequency at the 550 low end or the 1600 high end. An FM portable wouldn't work well, but a radio that tunes the aircraft band would work because that is AM. You can also use your car radio, which is what MikeBear did:
One channel issue, high VHF

Thanks for doing your FM report. It shows WRFY-FM that is about 67 dB stronger than WPVI. It is probably strong enough to overload a tuner or a preamp, but if you use an FM filter it will make WPVI weaker. The only solution I can think of is a custom notch filter designed to attenuate WRFY-FM without harming WPVI. Winegard used to make a tunable FM filter, the FT7600, but it is discontinued.

There are three other problems that might affect your reception of WPVI. The terrain profile shows that you are behind a hill for the WPVI signal:

You are in a dead zone for the WPVI signal. Red is a weak signal; no color is even weaker:

and it looks like some tall trees might be in the signal path; trees kill TV signals:

Attached Images
File Type: jpg Channel 6 Yagi.jpg (78.9 KB, 2397 views)
File Type: jpg MadMennoniteTVFp2WPVI.JPG (103.1 KB, 2048 views)
File Type: jpg MadMennoniteTVFcovWPVI.JPG (106.7 KB, 2081 views)
File Type: jpg MadMennoniteTVFtrees.JPG (124.2 KB, 2001 views)
If you can not measure it, you can not improve it.
Lord Kelvin, 1883

Last edited by rabbit73; 9-Jun-2016 at 2:58 PM.
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