[TowerTalk] Reliability (or not) of SMA connectors

[john at kk9a.com]

I agree, I cannot imagine wanting to Loctite or glue RF connectors. Start
with high quality connectors from a brand name manufacture such as Amphenol.
Make sure that they are properly installed on the cable. If they are
crimped, use the proper crimping tool. Tighten them with a 5/16 open end
wrench.  I don't see how it could loosen by itself inside the shack.

John KK9A


NA6O wrote:

I've worked on dozens of different airborne and army ground-mobile RF
assemblies over my career, as well as poking my nose inside many pieces of
commercial RF gear. SMA connectors were everywhere. NEVER have I seen or
heard of any kind of sealant, overcoat, or anything of the sort on any SMA
connector. Above all, putting anything inside the threads is simply asking
for trouble. TORQUE IT PROPERLY and be done with it. A quality SMA connector
is a high-precision machined assembly and must be treated with care. See the
old HP application note AN-326. They are in fact vibration-resistant when
correctly installed. Proper torque is also mandatory to avoid well-known
frequency response aberrations in the mid-GHz range due to waveguide
effects.

Of course, if your connectors are all crap and/or damaged, none of the above
applies...

Gary, NA6O


Pete Smith N4ZR wrote:

I'm not sure if this is the right place or not, but thought I'd ask 
because this is at least a feedline question.

I have a number of SMA connectors in areas of my station like my RBN SDR 
and my N1MM Spectrum Display.  It seems like every few weeks I start 
running into problems, and have to go through and retighten them to get 
rid of intermittent signal losses.  Is there anything that can be done 
to secure them better?

-- 
73, Pete N4ZR