> The first thing to try is to lengthen the coax between the amp and the
> transceiver.
>
> I would recommend that the cable be at least 20 feet in length, RG 8 type
> coax.
Yes, Dave Leason wrote a piece about this coax "transformer effect" several
years ago. His explanation, the coax "circuit" forms a double peaked, broad
band impedance match. I have forgotten the math, but recall it did make
sense. Others claimed all the coax did was introduce some loss,
in effect "fooling" the reflections into believing the mismatch was
not so bad. Such lossy padding is very common in microwave
circuits. But Dave's math did show loss is not the controlling
variable here, it is, in fact a broad band, double resonant
impedance transformation device which solves the match problem
Interesting stuff,
Best Jim W6KPI/KH6
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