[BC] mounting whips on vehicles

Tom Spencer Radiofreetom at gmail.com
Mon Nov 29 10:45:18 CST 2010


Well, with the whip horizontal, or nearly so, you can do "local skip" - NVIS, or Near Vertical Incidence Signals modes.  Of course, the  receive antenna has to be horizontal, as well... But it works reliably enough for the military.

Interesting to note that I've managed to receive AM 640 - the one that's running CC - at a range of about two miles, albeit in a rather narrow footprint.  My theory is that NVIS is exactly what I'm hearing.  I suspect if I had a "proper" antenna at both ends, It'd be surprised at just how much further I'd get by shooting the signal straight up.

As to using 26 MHz; a 20- or 30-foot fold-over/crank-up tower on a small trailer with a three-element beam?  Yeah, it'd take some setup time to unfold everything and get it aimed, but with practice, probably five to ten minutes.  I've had TV ENG shots that took almost as long to dial in, and from a lot closer than 75 - 100 miles out!  (I think the longest shot I did was about 60 or 70 miles - Crawfordsville, IN to the WTHR-13 tower at 96th & Ditch Rd on Indy's north side.  That one took a while to dial in - but it was still quicker than trying to get the physical tape back to the studio in time for the newscast.



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