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Old October 15th 07, 10:31 PM posted to rec.radio.amateur.antenna
[email protected] jgboyles@aol.com is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 58
Default Shunt loads on T-lines in EZNEC

On Oct 15, 2:55?pm, Cecil Moore wrote:
On my web page at:http://www.w5dxp.com/G5RV.HTM
I show how to install a 1000 pf capacitor across
the G5RV transmission line at the twinlead/coax
junction to improve the 75m SWR and move the
resonant point into the 75m phone band.

I have never been able to model the shunt capacitor
with EZNEC. Anyone know of a way to do that?
--
73, Cecil http://www.w5dxp.com


Hi Cecil, Looking at your webpage, looks to me like a 103' dipole
with 36-j324 impedance at 3.8 Mhz needs 28' of 450 ohm line instead of
300 ohm. 28' of 450 ohm line put you at 24+j25 with an swr of 2.7:1.
1000pf shunt cap. puts you near 1:1.

As for modeling the Shunt Capacitor, I have never done it, but you
might try a stub to simulate the Xc. Don't have time at the moment,
or I would give it a try.

73 Gary N4AST