Dave Platt wrote:

In article ,
Jeff Liebermann wrote:


That same diode-like effect also seems to be capable of causing the
cable to generate a nontrivial amount of broadband noise, when
energized by a sufficiently strong transmitter signal. In simplex
applications this seems not to matter, but in repeater applications it
tends to cause enough of an increase in the noise floor at the
receiver to appreciably de-sensitize the receiver.

The system I work on, was originally build with LMR-type feedlines
within the cabinet, and didn't "hear" particularly well. When the
chief hardware guru threw out all of those (well-constructed)
pigtails, and replaced them with 1/4" heliax... the problem went away
and has not returned.

Heliax is good. Double-braid shielded cable (with silver-plated
copper braid, not aluminum) seems to be almost as good.


Interesting. I always hear people bragging about LMR. Are we using the
term "Heliax" generically? Is semi-flex no good too, (It's all aluminum
and brass metallically isn't it?)

Did your guru make a profit on the replacement cables? How do you know a
$15 can of Cramolin wouldn't have helped just as much?

Tinned copper braid is OK, no?

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