[Elecraft] KPA100 SO-239 Help

[Ron D'Eau Claire]

Yes, that's one of the serious weaknesses of the "UHF" connectors, IMHO.
I've not had any trouble spinning the center pin enough to cause trouble but
if the outer shell is not screwed tight to hold the connector sections
snugly, one has an unstable and intermittent ground connection in the coax.
That leads to all sorts of odd problems that can be tough to troubleshoot -
intermittent noise on receive, intermittent SWR jumping about on transmit
and even arcing while transmitting producing distorted audio, noise
sidebands, etc.  

For that reason I'm very careful to ensure those connectors are all *tight*.

Ron AC7AC


-----Original Message-----

> I cannot picture how you could "spin" the CENTER conductor. That would
> require twisting the coax attached to the male half.

Sure, it shouldn't happen if the op uses diligence in keeping all connectors

tight.  But if the PL-259 becomes loose and ever-so-slightly unmates from 
the SO-239, the retention "teeth" no longer inhibit connector rotation.  Any

lateral pressure from the cable, especially from large, inflexible cables, 
causes the SO-239 pin to rotate.

Paul, W9AC