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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