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Old June 19th 06, 04:43 PM posted to rec.radio.amateur.antenna
Cecil Moore
 
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Default Voltage vs. Current Balun - OCF Dipole

wrote:
If the current is unbalanced, this would mean current is likely to flow
on the coax then? So perhaps the reason a voltage balun is used is to
merely transform the impedance 6:1 and purposely allow the feedline to
radiate? The maker of the antenna (Buckmaster) doesn't indicate any
particular length of 50 ohm coax be used, but I saw a huge change in
SWR and bandwidth on the upper bands when I lowered the antenna by 5
feet. Maybe this explains the behavior I saw.


The Carolina Windom is designed to radiate from the vertical
section of the feedline. You could duplicate that function
by installing a husky choke a few feet above ground. The MFJ-
853 is an inexpensive current meter that allows one to
measure the current on the coax braid. Mine arrived today.
It needs a little modification to allow the core to open
without needing the strength of Sampson.
--
73, Cecil
http://www.qsl.net/w5dxp