2. Rechecked all connectors to make them "wrench tight" All were tight to
the hand but about another 30 degrees of closure was gained by using a small
pipe wrench. Did not check clix at this time.
Uggh!
For any type of quality RF connector (this does NOT include "UHF"
PL-255/SO-239 connectors) with knurled shells, additional tightening
beyond finger tight does not help to make a better connection. Unless
the shell has flat surfaces, ie. like a hex nut, no tool other than
fingers should be used to tighten it.
If the shell is designed to be tightened with a wrench it is obvious,
since it looks like a hex nut. In that case the amount of torque used to
tighten it should be limited. There are special torque wrenches
available for this, but they are rather expensive. I suggest using
wrench with a handle no more than six inches long, and using only one or
two fingers to push the handle as you finish tightening it. DO NOT grab
the wrench in your hand and give it all you've got. Remember you are not
building an automobile engine, you are just connecting an RF cable.
Unfortunately with "UHF"/PL259 /SO239 connectors the tightness of the
shell DOES have an effect on the resistance of the outer conductor
connection. It does need to be tight, BUT with a clean, not corroded
connector, finger tight should be good enough. Any further tightening is
likely to do more harm than good.
If you insist, as many people do, on using a tool to tighten knurled
outer shells on coaxial connectors, then use pliers with soft plastic
jaws, so that you do not mar the connector. If you can't buy a pair of
plastic jaw pliers, then wrap some tape around the jaws of some regular
pliers.
DE N6KB
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