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AMfone's Online AM Handbook => Hints and Kinks => Topic started by: Steve - WB3HUZ on November 21, 2010, 08:22:02 PM



Title: Sealing PL-259 UHF Plugs and SO-239 UHF Connectors
Post by: Steve - WB3HUZ on November 21, 2010, 08:22:02 PM
http://www.arrl.org/arrlletter?issue=2010-11-18#toc05


Title: Re: Sealing PL-259 UHF Plugs and SO-239 UHF Connectors
Post by: k4kyv on November 21, 2010, 10:43:46 PM
Are they talking about regular SO-239s and PL-259s?  I thought "UHF connectors" were something totally different, special ones that look identical to 239s/259s from the outside, but have a concentric sleeve inside, and have a different nomenclature.


Title: Re: Sealing PL-259 UHF Plugs and SO-239 UHF Connectors
Post by: Pete, WA2CWA on November 21, 2010, 11:55:04 PM
Are they talking about regular SO-239s and PL-259s?  I thought "UHF connectors" were something totally different, special ones that look identical to 239s/259s from the outside, but have a concentric sleeve inside, and have a different nomenclature.

Some info as to why it was called a UHF connector: http://en.wikipedia.org/wiki/UHF_connector


Title: Re: Sealing PL-259 UHF Plugs and SO-239 UHF Connectors
Post by: k4kyv on November 22, 2010, 11:24:04 AM
OK.  The N connector is what I was thinking of.

I can understand why PL-259s might have been called "UHF" connectors when they were first developed, even though they are not really suitable for frequencies above 300 mc/s.  In the 30s and early 40s frequencies above 60 mc/s (or was it above 30 mc/s?) were referred to as "ultra high".  Check out any pre WW2 ARRL handbook. I suppose the name stuck with them after HF, VHF, UHF, SHF,etc. were formally defined after the War.

But I have never heard PL-259/SO-239s called "UHF" connectors in present-day literature or discussion.  I seem to recall the term being used for N connectors.


Title: Re: Sealing PL-259 UHF Plugs and SO-239 UHF Connectors
Post by: Pete, WA2CWA on November 22, 2010, 01:41:37 PM

But I have never heard PL-259/SO-239s called "UHF" connectors in present-day literature or discussion.  I seem to recall the term being used for N connectors.

Having dabbled in UHF frequencies for years, as far as I can remember, "N" connectors were always called "N" connectors.

From the Amphenol UHF Connector Series page:
http://www.amphenolrf.com/products/uhf.asp?N=0&sid=4CE9B280601AE17F&
And their UHF Connectors:
http://www.amphenolrf.com/search.asp?sid=4CE9B280601AE17F&N=57
You'll notice their wide variety and variations of PL-259/SO239 type connectors


Title: Re: Sealing PL-259 UHF Plugs and SO-239 UHF Connectors
Post by: ab3al on October 30, 2011, 06:16:37 PM
http://www.amazon.com/Mocap-Tape-Silicone-Hour-Stretch/dp/B00011Q872

i install commercial uplink 2 way satellite dishes... I found this stuff and its greeeeeeet.  and cheap.. i get it a little less through a dist.. no glue.. just wrap the connector back to about 1 inch past the connector and you have a weather proof seal... its not reenterable after one hot day but who cares.  theirs 36 foot on the roll


Title: Re: Sealing PL-259 UHF Plugs and SO-239 UHF Connectors
Post by: W0BTU on October 30, 2011, 06:40:52 PM
I gar-ran-tee you that if you do it the way I do, water absolutely cannot get inside your coax connectors.

I completely fill outdoor UHF (and F) connectors with silicone dielectric compound, and then tightly wrap the entire connection with electrical tape. As I wrap it, I stretch the tape so that it perfectly conforms to the connector.

I've taken such outdoor connectors apart years later, and the silver center pin/socket was just as shiny as when I assembled it; and there was no evidence of water or condensation.


Title: Re: Sealing PL-259 UHF Plugs and SO-239 UHF Connectors
Post by: Steve - K4HX on October 30, 2011, 08:12:57 PM
Yep. I do that too. Then I add a layer of coax seal followed by cold-shrink tape. It's probably overkill but it's as tight as drum. I've even buried cables with splices done this way and no water.


Title: Re: Sealing PL-259 UHF Plugs and SO-239 UHF Connectors
Post by: n2bc on October 31, 2011, 08:00:33 AM
I have had excellent results using electricians "Duct Seal".  It is available at the DIY stores & electrical supply stores, comes in 1lb and 5lb bricks.... my 5lb brick is at least 25 years old and just as flexible as it was on day one.

Two advantages over coax seal....  cost:  <$3/lb     cleanup: while it does a terrific job, it can be easily removed after years (decades) without leaving a sticky mess like coax seal.

I wrap the connector in duct seal then wrap the whole thing with Scotch 33+ or 88 tape, lasts forever.
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