Easy and cheap option (instead of Teflon insulation): use polyethylene
insulated wire. Almost all of the outdoor-type telephone wire is of this type.
It's the PVC insulated wire that typically deteriorates outside. Polyethylene
has a much longer life outdoors, especially the black stuff which generally is
uv stabilized.
-Bill
Sent from my iPhone
On Jun 25, 2014, at 10:46 AM, "James Wolf" <jbwolf@comcast.net> wrote:
> One note of caution, based on personal experience.
>
> I used some coated stranded #20 ga. wire here for my radials, and also for a
> electric dog fence. A couple years later, during the winter the dog fence
> opened up. I fixed it and it failed about three more times until spring.
> All the wire in both cases was initially laying on top the ground but over a
> couple years had migrated down about 1/2 inch or so. What I found was that
> over time the insulation had become very hard and cracked, more so in the
> damper area of the yard. This allowed water to ingress into the tin coated
> copper and eat the wire. This meant that I likely had a lot less of a
> radial field than I thought. I found some Teflon coated wire at a hamfest
> and am using that for the radials and the dog fence. After 20 some years
> now, no failures on the dog fence, so I'm pretty confident that the radial
> field is still mostly intact.
> I suspect that the insulation was compromised due to moisture, and it
> certainly was not suitable for outdoor burial.
>
> Jim - KR9U
>
>
>
> -----Original Message-----
> From: Topband [mailto:topband-bounces@contesting.com] On Behalf Of rich
> kennedy via Topband
> Sent: Wednesday, June 25, 2014 7:30 AM
> To: topband
> Subject: Topband: Deployable radials for 80/160M - Summary
>
> Thanks to all who have responded, both to this reflector and to me directly
> to my question ("... is #22 wire suitable for ~90' deployable radials ...")
>
> 1. Most recommend that unless there is some type of animal, person, or
> vehicle traffic that would potentially cross back-and-forth across the
> radial field that a #22 wire, especially insulated, should be OK. A few
> reported using a lighter gauge wire (#24 on down) with success. Wire size
> isn't a critical electrical variable in an installation such as mine (approx
> 40 wires).
>
> 2. If one is concerned about #1, then #20 or #18 should be your minimum.
>
> 3. Most, but not all, seemed to have purchased their radial wire from
> salvage, surplus, ham fests, thrift stores, etc. There seems to be multiple
> online sources (I google searched "surplus #22 wire") for all variations of
> wires (and wire from CAT 5 cable) suitable for radials.
>
> Regarding the question ("...spooling out radial wires, then re-spooling them
> in the spring ..."):
>
> 1. Wire 'flexibility' seems to be the concern - how easy is it to un-spool
> the radials, then to re-spool them without generating a tangled mess. If
> possible, wire insulation or jacket material should be examined and tested
> prior to the purchase. Know what you are buying.
>
> 2. Many users of deployable radials have purchased garden hose reel systems
> or an extension cord reel (a rotary wheel type device in a sturdy frame with
> a handle) - either the large (~2' x ~2') hose/cord variety or the smaller
> handheld reel/cord types.
>
> 3. Several users like to tie the individual radials in a sequence, one to
> the next, and twisting together the ends, for both deployment and
> re-spooling so that there is one long continuous piece of wire. One or two
> users built 'packages' of 2, 4, or even 6 wires all in parallel, especially
> where the radial lengths are nearly identical. If one has radial wires of
> multiple length, then he/she may want to consider color-coding the wire
> groups of different lengths (or using a spray paint the ends) to 'label'
> them for next seasons lowband operation.
>
> Apologies to those whose valid suggestions may have been left out of this
> summary.
>
>
>
>
> 73, Rich, K3VAT
> _________________
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>
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