[TowerTalk] SO-239 Problem

[jimlux]

Paul Sturpe wrote:
> BACKGROUND:  I have had several instances where a PL-259 loses contact with
> an SO-239.  I am told the problem occurs when a PL-259 is improperly
> prepared, leaving extra solder on the pin, thus making it oversized.   Once
> inserted into the SO-239 the center female connector expands.  Then when a
> properly prepared PL-259 is inserted into the same SO-239, the center pin
> connection is not snug enough to maintain proper contact because the SO-239
> center female contact never returns to its original size.
>  
> QUESTIONS:  Is there a way to repair a damaged SO-239 or once damaged, does
> it need to be replaced?  Are there SO-239s that are more tolerant to being
> oversized, i.e. certain brands?  Are there any simple ways to check for the
> proper size of the PL-259 before inserting it into an SO-239?  Are there any
> tricks to make the mating of the PL-259 and SO-239 less susceptible to the
> phenomenon I am describing?
>  
> Paul, W3GQ
> 

first off, this is a problem with lots of kinds of connectors, and it's 
particularly a problem in the microwave area, where thousandths of an 
inch make a difference.  (improperly assembled SMA connectors mated with 
K connectors and ruining the latter are notorious).

The two approaches used are:
"connector savers" A male/female adapter that you leave installed on the 
fixed connector. If all goes wrong and you screw up the connector, you 
replace the connector saver.  This is useful if the adapter costs much 
less than the fixed connector (we do it on spaceflight hardware, where 
the cost to replace a damaged connector is mind boggling (you might have 
to repeat all the shake and bake environmental tests), so the $100 for 
the M/F adapter isn't a big deal)

"connector gauges" which you use to check a connector before mating it 
(or more usually, right after assembling the connector in the first place).

Jim, W6RMK