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Old April 9th 07, 06:14 PM posted to rec.radio.amateur.antenna
Rick[_3_] Rick[_3_] is offline
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First recorded activity by RadioBanter: Mar 2007
Posts: 41
Default What kind of 1/2 wave antenna is this?


Way back in the good old days, I had a situation where I couldn't
center-feed an antenna, and couldn't use any kind of end-fed antenna that
required a ground system. So, I built an antenna that's described below.

1/4 wavelength of wire going to two egg insulators. Off of one of the egg
insulators is another 1/4 wavelength of rope. The feedline (coax) is
taped to the rope along its length, then the rope and feedline combination
is enclosed in 1/4 wavelength of copper braid. The center conductor of
the feedline goes to the wire, and the shield goes to the braid.

This then becomes for all practical purposes a 1/2 wavelength end-fed,
which is actually a center-fed because that's where the coax center
conductor is actually connected. Unlike a traditional center-fed dipole,
you don't need to worry about running the coax away at right angles for a
certain distance.

I seem to recall that this antenna worked pretty well on 20 meters but I
really had nothing to compare it with, and I only ran 50 watts anyway so
didn't get much DX.

I vaguely recall this antenna being referred to as a "bazooka" but I have
since seen the term "bazooka" applied to something else (e.g.
http://www.hamuniverse.com/bazooka.html), and mostly all I see is
references to a "double bazooka" (is there a single bazooka?).

Does this ring any bells with any of you?

Where can I buy braid that will be suitable? Most braid I've seen is flat
and if it can be rounded out at all (so that things can be inserted inside
the braid), doing so over a 1/4 wavelength on 40 or 20 would be very
difficult.

Thanks...