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Old March 11th 06, 09:00 PM posted to rec.radio.amateur.antenna
Dick, AA5VU
 
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Default Dipole Extension (done)

In article
,
"Dick, AA5VU" wrote:

In article T8mQf.913$_f4.191@trnddc03,
"Dale Parfitt" wrote:

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


Late yesterday afternoon I decided to try the two alligator clips and
some wire to run a test to see what would happen. Sounds easy but I
made it very hard. To make a long shaggy-dog story short I added the
wire and the SWR went out of sight. It acted like a dead short. I then
lowered he antenna and cut the wire in half and it was still terrible.
I then trashed he alligator clips and wire to and it was still
terrible. After two hours of screwing around, I found some dummy (me)
had the coax switch on the old Ringo Ranger rather than the W9INN
antenna. By this time it was too dark to mess with anything.

Going to start over when the sun comes up but this time I plan to ditch
the alligator clips and attach a one foot wire using the connection nuts
on the coil/trap or whatever w9inn used to call that thing between the
40 and 80 wires and will have the coax switch on the right antenna this
time.

Dick AA5VU (red-faced)


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.

7.600 1.8
7.500 1.4 2.0
7.400 1.1 1.8
7.300 1.1 1.3
7.200 1.4 1.1
7.100 1.7 1.1
7.050 1.8 1.3
7.000 1.8 1.4
6.900 2.0 1.6
6.800 - 2.0

The 50 MHz, 18 MHz, 24 MHz and 3.9 MHz readings did not change and
they are all 1.1 or very close.

Bill, W9INN, will be missed. He was a great guy and his antennas were
excellent. Too bad nobody picked up the ball from him. My old 40/80
W9INN has been modified to add WARC bands but still works great after 20
years of use and abuse. The traps are still in good shape.

TNX for reading

73, Dick AA5VU