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Peter Voelpel | all galleries >> Antennas >> Tower, total height 53m > assembling the 40m beam
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13-NOV-2005

assembling the 40m beam

The yagi will mount at the 38m level, on my location that is a better place then at 41m.
It is gamma matched and has good bandwith from 7000 up to 72ooKHz.
The yagi is originally manufatured by CueDee and was used on my former qth, boomlenght is 12m.
Simulation with AO showed a possible 0.6db improvement in gain and slightly better F/R but with that I would not be able to reach the driven element for adjustsments any more and needed to counterweight the boom for mechanical balance, so I made no changes.
Another gamma match consisting of two copper ropes 40cm apart left and right of the boom and 4,30m long is used on 80m together with a vacuum variable gamma capacitor ~200pf.
SWR2 points are at 3.74 and 3.85 2m above ground with SWR1.2 at 3.79MHz.
I hope it will tune that nicely 38m above ground

Medion 636Z3
1/300s f/2.8 iso100 full exif

other sizes: small medium large original auto
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