Topband: Half or Quarter Wave??

Jim Brown jim at audiosystemsgroup.com
Fri Jan 6 10:53:40 PST 2012


On 1/5/2012 8:35 AM, paul ecker wrote:
> Have a LDG Z11Pro auto tuner at base of pine tree that vertical leg runs up. 4:1 balun at base of vertical feeding RG-213 coax to shack.

I don't understand why the 4:1 balun, or the remoting the tuner to the 
base of the tree -- the feedpoint ought to be pretty close to 40-50 ohms 
as it is, and not terribly far from resonance, so the SWR with it 
feeding 50 ohm coax ought to be fairly low (less than 4:1). With this 
sort of condition, RG8 from the feedpoint to a tuner in the shack ought 
to provide a very low loss condition and handle legal ham power.  As it 
is, that 4:1 impedance transformation is likely to be adding loss rather 
than reducing it.

73, Jim K9YC



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