[222mhz] Cost/performance comparisons of transmission lines.

[Christopher Boone]

ScotchKote works fine for URD (underground residential distribution) but in sunlight, it is crap.
UV will destroy the ScotchKote over time....I too used to use it on antenna connections.....but after
doing a VHF Yagi at one of my dispatcher areas that way, and less than a year later, we found it all
GONE! (flaked off actually).

1/2in and 3/4in Aluminum jacketed CATV line works fine if you weather proof it and use connectors that
are not dissimilar that much....I prefer to use BRASS couplers between the jacket and say a PL 259...
One layer of Scotch 33 or 88 and then DUX or COAX seal and then more Scotch tape and it lasts as 
long as the connector does!

Chris
WB5ITT
Sr Telecom Tech for Entergy/Gulf States Utilities 1984-1996

-----Original Message-----
From: "Dr. Gerald N. Johnson, electrical engineer" <geraldj@isunet.net>
Sent: Dec 1, 2003 8:46 AM
To: n7eoj@arrl.net
Cc: 222mhz@mailman.qth.net, jmlowman@sbcglobal.net
Subject: Re: [222mhz] Cost/performance comparisons of transmission lines.

When KI0Q put that coax up, he waterproofed the
connections the say way he waterproofs aluminum underground service
wires with several layers of alternating Scotch 33 and Scotchkote. Today
there are heatshrink kits that would be at least as effective. 9913
can't be allowed to breath or it will gather moisture and there will be
condensation and that will cause loss that may not show up as SWR
(especially at 445 MHz).

I've been using 1/2" and 3/4" CATV 75 ohm cable at home for decades with
fine results, but I build my own connectors that use a large connecting
area on the aluminum shield with aluminum conductor grease and lots of
Scotch 33 for water proofing.

73, Jerry, K0CQ