I found that by feeding a pennant with a 1/4 wave (electrical) of 300
ohm twin lead and then a short run of RG-58 with a choke coil of 30
turns worked exceptionally well for me. This takes care of the
impedance transformation as well.
On the other hand some time ago I had a nice run of 70 ohm triax where
in I floated the far end and had both sheilds connected at the shack to
form a Faraday shield. This seemed to reduce the coax pickup
considerably as the coax (actually tri-ax) was 1/4 wave length long
electrically.
I did not make any A/B tests but probably should have to give real world
results. I did this because I was in the close proximity of a 5 kW BC
station and wanted to cut down on stray pickup as much as possible.
Herb (ex-KV4FZ)
St. Crook, VI
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