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Old March 11th 06, 10:16 PM posted to rec.radio.amateur.antenna
Dale Parfitt
 
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Default Dipole Extension (done)



I am not familair with this antenna, but if it has a choke/trap for
40M,
just add a foot of wire on the side of the choke/trap that is closest
to
the
center insulator- let it hang down and dangle. You can clip it on as
one
poster said- this is a high Z point and contact resistance is a
non-issue.
But as others have said, the on-air difference is zero.

Dale W4OP



The antenna now lives! This morning I added a 14-inch wire to each leg
by attaching it to nut on the 40 meter side of coil/trap thing. The
experiment worked so I know how much I need to cut and solder in on he
40 meter dipole. I may run with the 14-inch wire whips for a week or so
and see what happens. The following is a list of the before and after
SWR readings. The 14" addition did just what the book said it would do.
I now have the 40 meter resonant point pretty close to where I want it
for PSK and RTTY but can still use the phone band as well.

Absolutely zero reason to place that wire in series with the dipole- in fact
it will not yield the same results if you do so- you will end up having to
redo the length. It will also mechanically weaken the antenna and also
change 80M resonance. There is no current in that short stub-i.e. no effect
on radiation. Let it dangle.
Dale W4OP