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Old 20-Mar-2021, 10:07 PM   #4
rabbit73
Retired A/V Tech
 
Join Date: Aug 2012
Location: S.E. VA
Posts: 2,725
Quote:
Originally Posted by toddbailey View Post
the stations i want to receive are kstw 11, kffv (44-1 / 16) and kcpq (13 & 22)
currently kstw and kcpq are marginal, kffv is a no show
Thank you for the signal report.





9-1 (9) KCTS and 11-1 (11) KSTW are both listed at about the same strength; but you receive KCTS better. KCTS is licensed in Seattle and KSTW licensed in Tacoma, but the towers are close together in Seattle on Capitol Hill.



The original 4228 was designed primarily for UHF signals, but it has some useful gain on VHF-High (7-13).



KCTS and KSTW have a similar terrain profile; there is a hill in the signal path:



KCTS is running 21.7 kW ERP to an non-directional antenna and KSTW is running 100kW ERP to a very directional antenna that sends much less than 100 kW in your direction.

I suspect that the KSTW signal is weaker at your location because of the slightly different signal path, the signal diffraction at the crest of the hill, and the trees surrounding your location.

If you want to improve the reception of KSTW, you will need a separate antenna designed for VHF-High like the Stellar Labs 30-2476 or 30-2475. This antenna should also improve the reception of 13-1 (13) KCPQ. Try it without its own preamp first.

KFFV is much weaker. If you are not able to receive it with your 4228 antenna aimed at 238 deg true, you could try adding a medium gain preamp at the antenna. The risk is that the much stronger signals from the south might cause overload even though they are in a different direction.

A last resort for WFFV would be a third separate antenna for UHF like the Antennas Direct 91XG or Solid Signal HDB91X with a custom bandpass filter for channel 16 and a preamp.
Attached Images
File Type: jpg toddbaileyTVFmap_1.jpg (205.3 KB, 322 views)
File Type: png toddbaileyTVFreportRE.png (316.3 KB, 329 views)
File Type: jpg toddbaileyTVFseattleTowers_1.jpg (208.1 KB, 325 views)
File Type: jpg CM4228origForVHF3.jpg (189.8 KB, 320 views)
File Type: jpg toddbaileyTVFp3KSTW.jpg (92.4 KB, 321 views)
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Last edited by rabbit73; 21-Mar-2021 at 12:54 AM.
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