Toni Baertschi schrieb:
>From HB9ASB, JN36pt
PS. Actually it is very cold here and my antenna de-tunes from hour to
hour as the soil is freezing deeper and deeper. Not only the resonance
goes higher, the impedance is also changing and it is difficult to
follow this developement with the existing matching circuit.
Now, during winter time I can make the same observations. Before I have just
experienced small changes in resonance, but now, in the cold, not only resonance
changes considerably but also VSWR increases to S = 2 at optimum tune (I am
using a 50 ohms feeder cable between PA and LF antenna). Therefore I also have
to revise my fine tuning and matching circuitry to cope with these effects.
73 Ha-Jo, DJ1ZB
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