ac5e@comcast.net wrote:
I definitely agree with Sinisa. I have tried direct feeding an antenna,
starting with the antenna terminial on an ARC5 around 1948 or '49, and
never had much luck with it. Except at picking up a remarkable number of
minor but painful RF burns along the way.
So even a relatively short transmission line, with some means to keep
RF out of the shack if that's needed, is much better than no transmission
line at all.
73 Pete Allen AC5E
I have to respectfully differ.
I direct-fed a longwire from an older tube rig and experienced the
RF nibbling at my lips ... but the solution was readily found.
1. A good chassis ground.
2. A multiband counterpoise.
I was renting a second-floor room while at the Seminary and my
desk was back-to-back with the bathroom. A small hole through the
wall provided access to the cold water pipe for the ground.
I then acquired some multi-wire flat rotor control cable and cut
the far ends to 1/4 wave on the Ham bands (and taped them) --
problem solved and performance noticably increased.
Toroids, etc. may be a more elegant solution but I wonder about
potential efficiency as I am guessing energy is lost on transmit
via heat in the toroid.
IMHO, YMMV ... ;-) doc
--
Thanks! & 73, doc kd4e
West Central Florida
Atlas, Drake, Hallicrafters, TenTec ...
Non-Linux compatible PC's are inferior.
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