Quote:
Originally Posted by Tower Guy
WNYT-18 is at 183 degrees true, WMFP is at 121. The difference is 62 degrees.
A half wavelength on channel 18 is 11.88 inches.
If you build two right angle extensions and position the top antenna more toward WMFP and the bottom antenna further from WMFP, there is a magic distance when WNYT will be in phase while WMFP is out of phase. That distance is 1/sine62 * 11.88 inches = 13.45 inches. Therefore boom two offsets of 6.7 inches, one left and one right of the mast, and you'd drop the signal strength of WMFP by 15-20 db while not changing the signal strength of the main beam on any frequency.
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WHY?.....would even think about doubting you, chief? That little magic trick worked slicker then snot!!!! And it's two-fold, I'll explain...
I started by removing the RF 13 only antenna, as it seemed to be the logical offender being so close to the phased pair. Before I did that, all stations were normal, including WNYA RF 13, and RF 18 was gone, as expected.
I dropped the channel 6 only antenna down as far as I could without having to swap the coax out to a longer coax. The result was that all remained the same, except now I've lost WNYA as well as RF 18.
I had the volume up on the TV, tuned to RF 18, front door open. I pulled the lower log antenna out to create the "V" configuration, suddenly, I could hear The Today Show audio coming from the TV!!!
RF 18 was weak, but it was there, solid.
I spent the rest of the day tweeking, looking for the best "V" split, but settled on the above. Does it look squirrely? Yup...but it works.
The other benefit...I don't know if I've mentioned it, but WVNY, RF 13 in Burlington has always desensed WNYA RF 13 in Albany, not strong enough to lock, it just desensed WNYA, hence the addition of the RF 13 only yagi, which worked quite well to stablize WNYA. With this new config, it seems the phasing effect off the back of the beams has reduced the ability for WVNY to interfere with WNYA, RF 13 was on the air and very strong. AMAZING!
As you said, all stations seem to have the same SS after the change, except WCAX and WPTZ may have dropped a few SS units (afterall, we're talking 91 miles out), but being they were so strong to begin with, a slight reduction in SS makes no difference.
I appreciate your help, chief
Thanks.