Let me add to Pete's comments. I use 2 CAT5 cables in parallel for the rotor
cabling and use thicknet Ethernet cable (Belden 89880 orange jacket, triple
shield, 50 ohm) for feedline, with a short piece of RG-213 for the rotor loop.
The cable specs are reasonable and price is usually right - free. If it's used
- pulled to put in fibre - there may be vampire tap breaks in the jacket to
work around. UV resistance is unknown as the orange fades (not a bad thing -
ugly and obvious), but have yet to see signs of water ingress from jacket
deterioration, other than from improperly sealed coax connectors. I do replace
cables - Ethernet or RG-XXX - every 5-7 years whether they need it or not given
the amount of acid rain we get. Also I throw the analyzer on the feedlines to
see if things "look different" an ohm meter on the rotor lines before an annual
inspection to determine how much work may be needed. Of course, YKMV (metric
version)
Pete - can you post the URLs?
--
73, George VE3YV / K8HI
------------------------------
Message: 10
Date: Wed, 14 Nov 2007 07:31:28 -0500
From: Pete Smith <n4zr@contesting.com>
Subject: [TowerTalk] network cable outdoors
To: towertalk@contesting.com
Message-ID: <6.2.0.14.2.20071114071948.09cf4420@mail.comcast.net>
Content-Type: text/plain; charset="us-ascii"; format=flowed
I just saw an item in the ARRL Contest Rate Sheet recommending a couple of
URLs on this subject. Both say that ordinary indoor network cable will
deteriorate quickly outdoors.
That's probably true for fast data, but I have been using both 4-conductor
indoor telephone cable and 8-conductor indoor CAT3 networking cable for
connections between my shack and my tower some 200 feet away for the last
7-8 years. I control two TopTen 6-way relay boxes, an array of A/B
selectors, and a homebrew 80m array switchbox through these cables. I had
to boost the shack-end voltage to about 14 volts to get reliable relay
switching at the tower end, but in terms of reliability I'm quite
satisfied. The cables are simply laid on the ground in brushy woods, and
the only reliability problems I have had result from squirrels or chipmunks
chewing on the cables - and that has only happened once. Of course, the
cables fairly quickly become covered with leaves and grass, which no doubt
helps with UV, but so long as the outer jacket remains intact, no problem.
Strangely enough, 14-3 UF-B "Romex", which I use for rotator power, has
been far more of a problem. One of my rotator cables has developed some
leakage between the motor and indicator lines, causing some indicator
errors when motor power is on. Looking at the jacket, there has been some
fairly serious deterioration from UV. With the current price of copper,
buying 1000 feet of 14-3 fills me with terror, but I may be approaching
that time.
I just thought others might find this information useful.
73, Pete N4ZR
The World HF Contest Station Database
Full details on 3300 contest stations
Updated 5/5/07 http://www.pvrc.org/WCSD/WCSDsearch.htm
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