Eric SENSI wrote:
> I tried several things at the outside too, choke at the base of the antenna,
> reduce or lengthen the coax cables to avoid to be close of a multiple of a
> half-wave long, MFJ-915 common mode filter, RF inquiry filter, ferrites
> around the cables inside the shack... etc ! No way... still that stupid
> problem.
It is true that some parts of Orion are not protected
particularly well against RF currents. These include
front panel, CPU, DSP, codecs and audio amplifiers.
However, your choice of antenna is, I believe, the main problem.
The standard G5RV suffers from strong common mode currents on
most bands. These currents cannot be suppressed well using chokes
because of wildly varying impedance levels...
If you insist on using the wire on all bands,
then the safe way would be to use the twin lead
all the way down to the shack (not just some "magic" length),
and then use a symmetric coupler (a la Johnson Matchbox).
I have such a setup here and can run 1.5 kW safely.
73,
Sinisa YT1NT, VE3EA
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