[TowerTalk] [wwdxc] RG213 Woes

[K7LXC at aol.com]

In a message dated 7/19/2007 1:06:42 A.M. Pacific Daylight Time,  
wwdxc at yahoogroups.com writes:
 
    >  I forgot to mention, also, that the  use of barrel
connectors is discouraged, particularly in outdoor
runs.  Somehow corrosion always seems to occur in these
connectors, causing the swr  (and losses) to rise.
 
        I think the gist of this  thread is weatherproofing. I've installed 
dozens (hundreds?) of barrel connector  and other coax joints over the years 
and don't know of any that've failed. Most  amateurs make one or more mistakes 
when weatherproofing coax joints. 
 
        First, use 3M 33 or 88  tape. The 3 for a buck stuff from the 
hardware store won't cut it. 
 
        Next, use 2 pairs of  pliers to seat the connectors to the barrel 
connector. I'm not talking about  deforming the PL259 - it's just that finger 
tight is not enough.
 
        Wrap 2-3 wraps of tape  over the joint. Use a 50% overlap. Apply 
vapor wrap (butyl rubber - there are a  number of variations) over the joint. Wrap 
2 more layers of tape over the vapor  wrap. If the coax runs vertically, the 
last wrap should go up. That'll make the  water run off like shingles on a 
roof. Wrapped the other way and you've got a  perfect duct for the water to get 
into the connection. 
 
        Jim, you said you used  these materials but maybe there was a step 
you missed or something. Following  the above scenario will give you a bombproof 
joint. Even leaving off the vapor  wrap will still result in a reliable 
weatherproof connection. Some commercial  installers spray the finished joint with 
clear Krylon spray paint which is  more belt-and-suspenders approach. 
ScotchKote has been used in the past but it's  really for buried connections and will 
dry up and flake off when used in an  outdoor application like this.
 
Cheers & GL,
Steve     K7LXC
TOWER TECH -
Professional tower services for hams
Cell: 206-890-4188


 



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