[TowerTalk] Fw: Amphenol PL259

[Steve Katz]

At work for over 26 years we put a small washer in the PL259 so the reducer mashes the shield tight between the body and reducer as it is screwed in. We never solder the shield. After all, even the center pin of the PL259 is only a pressure fit in the SO239. In 26 years and 1000's of mobile coaxes installed we never had a problem doing it this way. This is much more foolproof than soldering and heating (melting) the center insulation. Larsen antennas use to come with a Teflon washer in the PL259 bag! Teflon or plastic worked fine, but I have also used very small metal washers. 

::I've never had any problem soldering the braid through the solder holes, flowing solder through the braid and into the surface of the reducer.  It takes five seconds with the right soldering equipment and results in a very strong bond without overheating anything.  Keywords, "right soldering equipment."  :-)

As for RG213 or RG8, we ALWAYS fold the shield back over the outside jacket and screw the outer body of the PL239 over the shield, smashing the shield between the outer jacket and the body's threads, then cut the shield that sticks out with a knife held tight against the body and turn the body, it cuts it nice and flush. We (of course) solder the center pin. This has been 100% reliable and works better than soldering. Also, it is easer to get new guys to do it right 100% of the time than the soldering/melting way. On antennas up in the air it holds the coax in the connector MUCH better than it hanging from only the shield, poorly soldered at best. I know you need a strain relief, but on mountain tops with ice you need all the help you can get.
Not wanting to start a debate, but this works, I know it works, and for us it works best.

::No debating.  But this introduces a larger impedance discontinuity than doing it the way the connector was designed to be used, where the cable's outer conductor continues up inside the connector body until it is within 1/16" or less of bottoming out against the dielectric material inside the connector.  On HF, it probably makes no difference one way or another.  At VHF, it makes quite a difference.  I routinely sweep UHF cable assemblies to 300 MHz, and with a 1.2 GHz Termaline for a termination, get ~30 dB return loss at 300 MHz on most dual-UHF connector cable assemblies (short patch cables); using the "fold the shield back over the jacket" method described above, that drops to 10-12 dB at 300 MHz.  Still  not "terrible," but not nearly as good as 30 dB.  The difference is obvious and repeatable.  For those of us using these connectors at 144 and 222 MHz, it's worth doing it the old fashioned way.

WB2WIK/6