Just old. They went up 10 years ago (Oct. 2005), two have actual splices
with barrel connectors in them and this bend. No SWR issues or anything. All
RG-213/U non-contaminating jacket, 95%+ braid. The cable bundle has been up
and down hundreds of times, bundles lay on the ground and even in the snow
in the winter since there's no really good way to secure them with the tower
down. I'm guessing they're nearing the end of life by now.
I had thought about putting up LDF4-50 hardline but was dissuaded from doing
so by a number of people I trust-I have a 40' run from the shack to the
switchbox and four 75 to 90' runs up the tower to the Yagis (and 80m vee).
- pjd
From: K7LXC@aol.com [mailto:K7LXC@aol.com]
Sent: Thursday, June 04, 2015 2:07 PM
To: towertalk@contesting.com; contesting@w2irt.net
Subject: Re: [TowerTalk] 90 degree coax bend atop a crankup tower
> Is there a preferred method of routing cables that doesn?t involve a
sharp
bend like that? I?m imagining there?s quite a nasty impedance bump going on
here, not to mention the potential for physical damage to the dielectric in
the heat and cold, etc.
There are a couple of schemes for a larger bending radius - I think
Chris, KF7P has one. I've installed dozens of crank-ups and guyed towers
with hundreds of feedlines with the same technique of just dropping them
over the edge and I've experienced zero failures that I know of.
The only coax I'd worry about are the ones with foam cores - they can
cold flow over time and cause the aforementioned impedance bump, perhaps
even failure in extreme instances.
> If I?m going to spend hundreds of dollars in new feedline, plus the
costs of having it installed (I cannot climb, myself)
Was there a problem with the existing feedlines or are you just
replacing them because they're old? I'm a big proponent of "If it ain't
broke, don't fix it". I don't want to discourage your from spending money
but maybe this is a very discretionary project that has more psychological
benefit than actual operational improvement.
Cheers,
Steve K7LXC
TOWER TECH -
Professional tower services for amateurs
Cell: 206-890-4188
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