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Old May 4th 07, 04:08 PM posted to rec.radio.cb
james james is offline
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First recorded activity by RadioBanter: Sep 2006
Posts: 298
Default Hey Antenna Gurus !

On 4 May 2007 05:46:49 -0700, Telstar Electronics
wrote:

+++On May 4, 6:51 am, james wrote:
+++ Tomatch an antenna that is around 100 Ohms impedance needs only what
+++ is called a quarter wave matching stub. It is simply an electrical
+++ quarterwave length of 75 Ohm coax from the feedpoint to the 50Ohm
+++ transmission line.
+++ Simple and works well.
+++
+++Problem is... the stub would be quite long... about nine feet.
+++I wouldn't want that much coax kicking around as a matching network.
+++
+++www.telstar-electronics.com

**************

IF coax length is a hangup then you can use a two to one balun.
Actually the length will be between 66% and 80% of ~9 feet depending
on the dielectric constant of the material that comprises the coaxial
cable's center. Using RG11 polyethelene dielectric will yield about 6
feet.

Also considering that if you want vertical polarization the feedline
must come away from the feedpoint orthogonally the run of any length
of matching stub would be immaterial.

james