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Old 24-Aug-2013, 1:58 AM   #62
Pete Higgins
Pete Higgins's Avatar
Join Date: Apr 2013
Location: California, 58 miles @112 degrees from Mt. Wilson
Posts: 83

WOW! I don’t even want to know how long it took you to pull all this all together! I just hope you’re not going to bill me for it later?

This is great work and way beyond my ability to provide for the community; essential information for anybody considering multiple, same band, antennas. In addition to the expected <3 dB combining gain you’ve illustrated the importance antenna spacing can play. Again, clear concise and to the point.

I have a pretty good handle on LOS propagation and refraction extending the range to the “radio horizon”, multipath and even the “wavelet” concept that explains why we can receive diffracted signals that simple insight would suggest should be completely blocked. I even have a handle on how differences in the troposphere (temperature, water vapor, barometric pressure etc.) can cause tropospheric scattering. What I have trouble rapping my head around is which mechanism is responsible for what I see as channels fade both short term (multi-path?) & for hours at a time (tropospheric absorption?). I’m sure it has to be the “vector sum” of all these simultaneous mechanisms. I’m tempted to get a decent rotor and weld a plate into the top of my tower to support a “long mast“ and another 91XG. Other than it should work better though, I’m not really sure what to expect without trying it.

Those two RCA pre-amps. that I reported on worked out so well that my wife got after me to order two more. Ordered on Monday and received today. Since Time Warner blacked out CBS & CBS blocked Time Warner customers from downloading content (series episodes) from their website, my wife & I’ve been able to watch them from either San Diego or LA. I have also been able to let her watch the LA CBS evening news which she really prefers. Since I turned 70 last month, I had to go to the CA DMV and retake my driver’s license and motorcycle operator’s tests this afternoon so still need to bench check them tonight or tomorrow. I must have ordered two of the last ones because when I went back to the site they no longer list them.

Looking forward to your next post.
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