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Re: 9913 Coaxial Cable

Hi Gerry,

My 9913 70cm uplink, or rather, what remains of it, is
coiled up in the garage, waiting for a better use than
as an RF feed line.  For several years I sucked the water
out of it by drilling a small hole at the bottom end,
through the nylon/teflon/whatever insulator next to the
center pin in the N connector.  Used a syringe that our
vet gave us long ago for some sort of ailment on our cat.
Long curved pointy end that fit into the 1/16" hole.  Got
a couple of CCs out.

To be fair, I finally found the cause of all the water -
a squirrel had chewed through the insulation up near the
top by the antennas.  Hungry, I guess.  Too bad I wasn't
transmitting at the time...

Your symptoms, however, don't suggest moisture.  Antenna
position is not a moisture thing.  Sounds like a loose
connector somewhere, or if you have been flexing the
coax any, it's probably broken internally.

Your last sentence is the best suggestion - new LMR cable.
I got lucky and traded a spare antenna for some hardline.
Still haven't gotten it to work (bad connector, I guess).
Currently using some plain old RG-8 until I get around to
fixing it.

Good luck,

Greg  KO6TH

>From: Gerry <ve4gtb@mb.sympatico.ca>
>To: "amsat-bb@AMSAT.Org" <amsat-bb@AMSAT.Org>
>Subject: [amsat-bb] 9913 Coaxial Cable
>Date: Mon, 02 Sep 2002 09:12:01 -0500
>For the past 8 to 10 years I have been using 9913 (approx.100ft.) as my
>2mtr feedline .Lately I have been having problems ,as follows.
>When the weather is damp , or rainy and  the antennas are pointed in
>certain directions ( this seems to vary) I get a high SWR warning light
>. I have been told that this is a characteristic fault of this product,
>that it does absorb moisture internally.
>Now I need some help or comments on the following suggestion , that was
>given to me for a remedy to be used to attempt a fix for this problem. A
>25 watt lamp bulb is connected in series to the centre conductor ,120
>volts applied to light bulb with coax shield to ground .The idea I am
>told is if moisture has shorted out cable light will not come on. If
>light bulb has a dim glow then leave in this state for 24hrs or so.  As
>drying takes effect the light bulb should return to its natural
>The antennas are M2 2mtr. and 70cm mounted on a tripod , which is
>located atop of wooden garden shed .The cross-boom is fiberglass.
>My knowledge of electronics or electricity is if the wall switch is
>turned on , the lights should come on .
>The feed from the mast mounted PA to the antennas has been checked with
>MFJ analyzer and no problem, as soon as the 9913 connected (with mast
>mounted PA taken out of  line)
>the swr needle goes right off the scale.
>All connectors had been re weather proofed with coax sealant about a
>year ago. They did not show any signs of moisture penetration into the
>connector as this was one of the first areas we checked.
>Would appreciate any comments or suggestions,other than replace coax. I
>have ordered LMR 400 from local supplier.
>73 de Gerry ve4gtb
>Amsat membership number 29196
>Via the amsat-bb mailing list at AMSAT.ORG courtesy of AMSAT-NA.
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