On 12/10/2019 1:13 PM, john@kk9a.com wrote:
Of course I meant to say "with no issues" in my post. The nylon coating on
THHN does quickly deteriorate outdoors however I believe that the nylon's
purpose is to lessen friction and improve chemical resistance. Neither of
these are issues to me and the PVC underneath is pretty tough.
The 350 ft run to my Yaesu rotator are two 250 ft runs of #14-2 Romex
(plus ground) to the base of the tower, laying on the ground.
Transitioned to something smaller to go 120 ft up the tower. Nine years
so far with no issues.
I've used THHN extensively for wire antennas and radials. My current
favorite for high dipoles is bare #8 that is stretched to make it hard
drawn #9 -- attach one end to a fixed object and the other to the
trailer hitch on the SUV, pull slowing until it breaks.
A major advantage of using stretched wire is that un-stretched copper
will stretch under tension over years. Before changing to stretched
wire, I found that I had to circumcise my 80M dipoles (#10 THHN) every
few years to keep them on frequency. For my fan dipoles, I now use
stretched wire for the longest element that bears the pulling stress and
THHN for the shorter elements that do not.
73, Jim K9YC
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