Steve Weisbrod writes:
>What does burn up coax length to lower antenna mean???
>73 Steve W8GAZ
Stacked antennas need the same length of coax to each. The lower
antenna therefore will need to have the extra coax coiled up
somewhere...might as well be at the antenna as a 'black-magic' choke.
The question is which of the three choke designs, all using the same
specified RG213, is the RIGHT ONE.
73, Rick, N6CR
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Original Subject:
[TowerTalk] RE: Question on choke balun (black magic)
As long as someone brought up the subject of coax baluns for the
Cushcraft A3WS...
Can someone help me understand why:
Cushcraft specs 8 turns on a 6" diameter, which is a total of 13 feet,
for the A3WS.
HyGain, for their 12/17 duobander specs 12 turns, 6" diameter for a
total of 19 feet.
The ARRL Handbook wants 6.5 turns on a 5" diameter for a total of 8
feet for a 12/17 meter antenna.
Is all this just black magic? I have a very high degree of confidence
in HyGain testing and engineering as well as in W7EL, but the
difference in the balun sizes is far more than just academic. I would
agree that the simple ferite bead balun solution is MUCH better, but in
my case because of stacked antennas, I am trying to burn up coax length
to the lower antenna anyway--might as well just wind a balun...but to
what length on what diameter?
Any thoughts/opinions welcome...
73, Rick, N6CR - Atlanta
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