At 09:16 AM 1/15/00 -0700, measures wrote:
>As I understand it, Larry, some varieties of PVC are lossier than others.
> The best test I found was to hang a sample of the plastic about 6
>inches from the end of my 40m dipole. Sending ''dits'' with the
>''Plywood Box'' amplifier, common pvc would ignite in seconds. . Oddly
>enough, Less RF potential existed at the end of the antenna wire.
>
>cheers
>
>- Rich...,
Interesting test, Rich. I will have to give that a try. (Next time I have a
dipole!)
I have had excellent results using acrylic and/or polycarbonate materials
as end insulators and as inslators in the anode comparment as well. Too bad
those materials melt so easily! Another interesting material that bears a
close look for these applications is common PVC pipe cement. When
completely cured, this stuff is great! I use it to wx-proof the mobile
coils. Measurements of Q before and after coating the coils show little
difference. Does not seem to break down in the presence of RF. Don't know
what's really in the stuff, but it "looks like" a solvent similar to
acetone with a filler similar to polystyrene. Those are the basic componets
of the old "Q-dope".
Home Depot is a great place to shop for radio parts!
73,
Larry - W7IUV
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