[TenTec] Connector tightening

Randy Fulco rfulco at bellsouth.net
Wed Jul 27 14:15:21 PDT 2011

I saw that also...I went into my RainMan routine "oh no,  oh no".....

--- On Wed, 7/27/11, Ken Brown <ken.d.brown at hawaiiantel.net> wrote:

From: Ken Brown <ken.d.brown at hawaiiantel.net>
Subject: [TenTec] Connector tightening
To: "Discussion of Ten-Tec Equipment" <tentec at contesting.com>
Date: Wednesday, July 27, 2011, 1:15 PM

> 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.


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 

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