When you raised the antenna to 80', did you measure the resonant
frequency AT THE ANTENNA? .. or at the end of a piece of coax?
The ONLY way to 'get it right' is to do ALL measurements AT the antenna,
NOT down at the shack!
I agree with VE9AA who said you should 'tune' the antenna with the
reflector on the ground and pointing straight upward, but NOT leaning
against a metal support [tower, etc.].
If you set the antenna to the factory dimensions, it will work correctly
and resonate properly .. [have had two 205bas antennas that did] ..
please remember that the 205CA has radically changed spacing between the
elements compared to the 205BAS.
Good luck
Don - N8DE
Edwin Koch wrote:
>
> thanks for reading this. i have a 205ca that is driving me crazy. i set the
> antenna for low phone, 14.150 mhz. on the ground with the antenna on saw
> horses, the mfj 259 showed the resonant freq to be 13.650mhz.
> with the antenna at the top of the tower 80ft the resonant freq never
> changed, only the swr got much better. i have checked and rechecked all
> measurements at least six times. the only way to get the resonant freq where
> it belongs is to shorten the driven element up to where it is shorter than
> the first director. i read on e-ham where a guy put one together but couldnt
> get it up the tower in time for a contest, so left on the saw horses and
> worked a hundred contacts. i recently redone a 40 meter beam and set it to
> 7.050 . on the saw horses the resonant freq was correct just the swr high. i
> pulled up on the tram about 35 ft and the swr dropped to 1.5. this is the
> way i expected the 20 meter beam to work. i have tried a different balun, no
> balun and a new pig tail. even checked the mfj 259 to make sure it was on
> freq. any ideas???
>
> thanks in advance,
>
> ed n4ek
>
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