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
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