Vic Rosenthal wrote:
> I have been
> successfully using an old Johnson 275-watt (AM) matchbox to feed a 40-m
> dipole,
> ladder-line fed, on all bands at 800w CW for some time. I suspect that the KW
> version would be good for considerably more than 1500 watts PEP.
I forgot to add, for those who don't know, that the Matchboxes are link-coupled
parallel-tuned, balanced circuits. The 4 to 1 balun in most modern tuners is
very inefficient when the SWR on a balanced line gets above 3 to 1 or so. These
tuners are really designed for coax or for balanced lines which are 'flat' (like
a folded dipole fed with 300-ohm line).
73,
Vic, K2VCO
Fresno CA
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