I've heard from some guys that used hardline is a mistake in the
making. Well, that may be true in some cases but for most, it's
definitely worth checking out. Especially if it's 50 ohm stuff. Even 75
ohm can be used if trimmed in half-wave multiples, especially for the
higher and more narrow bands (%BW).
For some of the runs here, I'm using some 7/8 thick-walled aluminum
50-ohm stuff that I suspect came off a communications tower based on
periodic white & red paint marking. It has a residual date code in some
places that you can barely make out of the mid 80s. Center core is
solid aluminum with a copper plating. Found it setting in a farmers
field at a good friend of mine who passed away.
Like you, I stripped it back a bit and found the copper to be bright and
shiny. The foam material did not seem to ooze any water when I squeezed
it with a napkin to help detect trapped moisture. Assuming it had no
significant water content (which would have likely caused tarnished
copper), I did not test it for loss. Just used it.
The hardest part was unraveling and unrolling it - it's very heavy and
the coils were in bulk, not on a reel or anything.
To feed the 80m 4SQ, I did not try to put on a proper connector, instead
just hacked a pigtail of RG213 on each end, clamping to the outer
conductor with some conductive grease and a hose clamp - and soldering
the center conductor. A bunch of 3M tapes provided the weather seal.
Works great. Especially at the price. And I also have the peace of
mind that the cable is so mechanically massive it will never die short
of a monster lightning strike or similar - and it will probably be
working long after the more delicate Andrews stuff laying in the trench
next to it.
73/jeff/ac0c
alpha-charlie-zero-charlie
www.ac0c.com
On 11/14/19 12:11 PM, Hans Hammarquist via TowerTalk wrote:
Hi Bill,
I don't think you will have any problems with that. I would think that the cable
companies (or whoever ordered it in the first place) ordered anything that would
go bad in a short (<20 years) time.
You said there were no signs of oxidation a few inches from the ends and the
attenuation is well as expected. That's a good sign.
I'm using very old cable TV cables up my tower and that works well for both HF,
VHF, and TV (don't tell anyone).
I would think that the problems we had with coax cables from the war are taken
care of by now. The dielectric in my TV cable was white with no discoloration
unlike old coax from the war era that became yellow after some years and, by
then, lost some good characteristics like low loss.
Just my penny. 73 de,
Hans - N2JFS
-----Original Message-----
From: Ralston, William <William.Ralston@viasat.com>
To: towertalk@contesting.com <towertalk@contesting.com>; W4EF@dellroy.com
<W4EF@dellroy.com>
Sent: Wed, Nov 13, 2019 4:48 pm
Subject: Re: [TowerTalk] Old Hardline
Mike -
I bought a 1000' spool of ½ inch hardline circa 2000 of unknown age (I don't recall
the make, it wasn't Andrew, but it was compatible with the most common LDF4-50
connectors). I did note there was some oxidation of the copper near the cut ends,
but cut off a few inches or more to get to clean copper.
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