[TenTec] Re: End Fed Antennas [Was: Capture area]

[edoc <kd4e@arrl.net>]

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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