N6RK wrote: The real deciding factor to me was the discovery that if
any water
gets into the coax anywhere, if there is DC on the coax, there will
be a small DC leakage current that generates 40 dB over S9 noise. ....
Good point and very true. I had a similar experience with a receiving
antenna. I used barrel connectors to splice some 75 ohm cable along a
750 ft run. I cleaned the barrel connectors with WD40, a big mistake.
The WD40 left inside the barrel connector, because of its low surface
tension, floated crud out of the connector causing a high impedance
short (>20K ohms). That generated S9+ noise because of the DC signal on
the cable. The noise level was proportional to the DC voltage. Lesson
learned.
Jerry, K4SAV
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