Date: Mon, 25 May 2015 05:34:06 -0700
From: "J. Hunt via TowerTalk" <towertalk@contesting.com>
To: towertalk reflector <towertalk@contesting.com>
Subject: Re: [TowerTalk] sealing PL259's
I do not use PL-259's much outdoors (or indoors), the choice is N
connectors... on everything - 1.8 - 500mhz.
The N connector is weatherized, less impedance bump and higher power
capabilities.
... 7/16 Din connectors anyone ...
By design, the PL-259 is not weatherized.
A simple way of preventing water egress within any connector, is silicon
grease. Application is done during assembly and when installed onto the
device. Then multiple wraps of Scotch Super 33 electrical tape and Coax Seal.
So far, many years of trouble free service.
This process is little more expensive, but never had a failure yet.
Sorry, I am skeptical on garden hose washers.
Thanks N 73,
James
ki5dq
... A veteran tower dog ...
## I gave up on those stupid type N connectors years ago. Why bother using
em ? They come with a puny center pin that is virtually
identical to the center pin on a BNC connector. ALL the telcos and cell
companies have dumped the type N..and gone to a 7-16 DIN.
## If you want to see something absurd, look at .875 inch or 1.25 inch
heliax... or LMR-1200DB coax....with a type N connector. Coffee mug size
connector...
with this tiny BNC size pin. A SO-239 / PL-259... american made teflon
/silver type is a far better bet..and zero swr Z bump.
## I use 7-16 dins myself. The female chassis connector uses a 1.25 inch
square flange..with 4 x 8-32 SS screws. They are not much bigger than the 1
inch square flange
of a SO-239 or type N female chassis connector. However, the OD of the
female is huge.. 7mm. The mating pin is also huge..like the size of a .22
slug.
The ID of the mating RF connection is also huge... 16mm. They are water
proof. You wont blow em up any time soon..and most are good for 2800 v rms,
add 41% for the peak V. A type N is only rated for 500 vrms. A 7-16 din
is good up to 7 ghz. There are plenty of em now on the surplus market.
## On the bigger coax and heliax type cables... the cable makers now only
offer 2 x connector choices.... type N or 7-16 DIN. No brainer there.
LC connectors have gone out of vogue..and ditto with type C connectors.
## To seal any of these connectors..use silicone grease on both the threads
and a tiny bit on the pin. Then wrap with 33/88 tape...then quality heat
shrink,
like the T+B type..with the longitudinal ribs in it...and also the internal
glue glop. You can apply five times the torque on a 7-16 DIN vs a type N.
Dins
comes with red silicon rubber gasket seals.
later.... Jim VE7RF
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