Eugene Jensen wrote:
>
> I would use Davis RF Buryflex cable and I would put it inside polypipe,
> the good old stuff that sprinklers are used with; but I would just put
> the ends much higher than the pond, and seal it. I think that this
> would work out really nice and Davis RF is a great company to deal with.
> This way when your pond freezes, the compression will be against the
> polypipe and not against the actual RF cable. I wish you the best of
> luck and I have used a bunch of this on my tower successfully and it is
> some really bullet proof cable. I got burned a few years back by buying
> Belden 9913 within a couple of years, it all failed. Some of the worst
> cable I have ever owned, so it taught me my lesson about "you have to
> have a name brand!" 73's Gene K2QWD
>
> -----Original Message-----
> From: owner-towertalk@contesting.com
> [mailto:owner-towertalk@contesting.com] On Behalf Of WA9ALS - John
> Sent: Tuesday, October 23, 2001 7:00 AM
> To: towertalk@contesting.com
> Subject: [TowerTalk] Underwater coax
>
> I don't want to start a debate about whether this is a good idea, or
> which
> coax would be best. However, I would like some ideas about how to
> handle
> the points where the coax enters and exits the water.
>
> I'm going to run a feedline across a pond that the top 10-12 inches of
> which
> freezes each winter. Someone said I should use some PVC where the coax
> enters and exits the water to relieve compression forces at the freeze
> line.
> I can't picture how to do this - Seems like if I just put a PVC pipe
> there,
> it will fill to the surface level with water, and then that water inside
> the
> PVC will also freeze. And it seems the compressive force from the ice
> outside the PVC would translate through the pipe, through the ice inside
> of
> the pipe, and finally to the coax. Is there something I'm missing about
> how
> to do this with PVC pipe at the entrance and exit points?
>
> I suspect it would be functional for "quite a while" if I just let the
> coax
> take whatever nature has to offer, and it will be easy to replace if
> needed
> every few years (except for those "crappy PL-259s"!). But if there's
> something reasonable to do to protect it some more, I'd like to do it.
>
> Please read the first paragraph of this again, and then I'd be grateful
> for
> any constructive ideas. Thanks!
> ------------------------------------------------------------
> John - WA9ALS - VP5RY
>
> email: wa9als@starband.net
> homepage: http://www.qsl.net/wa9als (New - NCJ article on VP5 trip)
>
> List Sponsored by AN Wireless: AN Wireless handles Rohn tower systems,
> Trylon Titan towers, coax, hardline and more. Also check out our self
> supporting towers up to 100 feet for under $1500!!
> http://www.anwireless.com
>
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> List Sponsored by AN Wireless: AN Wireless handles Rohn tower systems,
> Trylon Titan towers, coax, hardline and more. Also check out our self
> supporting towers up to 100 feet for under $1500!! http://www.anwireless.com
>
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I would recommend you talk with Ed, W0SD, to get his advice. He has a
1/4 wave 160m vertical constructed of Rohn 25 base fed in a pond behind
his house. He most certainly will have good ideas on the feedline run
during the winter time from South Dakota, where the ice is very good
quality.
BTW, He and others are leaving for Ghana for DXpedition tomorrow 10/24.
See you in SS CW and SSB from W0SD, although probably not on 160!
73, best regard and God Bless!
todd,WD0T
List Sponsored by AN Wireless: AN Wireless handles Rohn tower systems,
Trylon Titan towers, coax, hardline and more. Also check out our self
supporting towers up to 100 feet for under $1500!! http://www.anwireless.com
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