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Windom & open wire feed line

Dec 10th 2015, 21:10

K2HRO

Joined: Apr 4th 1998, 00:00
Total Topics: 0
Total Posts: 0
I love my OCF antenna. It's only problem is the weight of the balun and copper feed line causes it to droop. I'd like to feed it with open line and put the balun a few feet above ground.

Problem is that nobody makes 200 ohm feed line. Has anybody tried 450 or 300 ohm line WITHOUT a tuner?
Dec 17th 2015, 12:05

W1VT

Joined: Apr 4th 1998, 00:00
Total Topics: 0
Total Posts: 0
http://www.w8ji.com/windom_off_center_fed.htm
This page by Tom W8JI suggests you can get a lower SWR using 300ohm line if you use a 137' wire with an 80% offset.
Since OCF dipoles interact with the feedline, results are even more variable than ordinary dipoles, both of which are affected by height above ground and the insulation on the wire.
There is also the variability in terminating the 300 ohm line with a 200 ohm balun.


Zack W1VT
ARRL Senior Lab Engineer

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