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Old 25-Mar-2020, 10:46 PM   #6
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Join Date: Nov 2014
Location: Acworth, GA
Posts: 271
Originally Posted by ADTech View Post
Unfortunately, with the upper antennas viewed against the sky, there's no reference scale so as to estimate the length of the elements or the boom.

Yeah, I'd also suspect amateur radio for those upper antennas. Maybe if an old-time amateur operator drops in, they might be able to comment.
The top set of beams looks to be a Cushcraft A26B2 beam installed with vertical polarization for the 144 to 148 MHz ham band. (It is essentially two of the Cushcraft A13B2 beams installed on a stacking boom and connected with a phasing harness.) Vertical antennas on this band are usually used for FM voice operation with handheld, mobile and base units. With this much gain they are most likely operating on simplex channels.

The beam just below it is a Cushcraft A13B2 beam installed with horizontal polarization, also for the 144-148 MHz ham band. Horizontal antennas are usually used for SSB (single sideband voice) and CW (Morse code).

Just for a reference, the booms on these antennas are 15 ft long and the elements are about 40 in long. It does look like one of the beams has slipped a bit on the mast and is pointing a little bit off.

Tim WS4V
Antennacraft Y10-7-13 VHF, Antennas Direct 91XG UHF
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