[Elecraft] KAT500 Tuning issue

[Don Wilhelm]

Assuming that the feedline is ladder line or open wire for low loss, add 
an eighth wavelength of feedline on 20 meters (about 8 feet). That may 
or may not help on 10 meters (the problem is thee same, the radiator has 
a very high impedance, and the feedline must be used as an impedance 
transformer to bring it down.   Maybe some work with the ARRL program 
TLW is in order.

73,
Don W3FPR

On 12/8/2012 4:14 PM, Vic Rosenthal wrote:
> If the feed line happens to be near an even multiple of a half wavelength the impedance will be very high and there will be a voltage loop (HV point) at the tuner. As someone else noted, losses would also be very high, so using a 40m coax fed dipole on 20 is a poor idea.
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> Vic k2vco
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