Tom, I saw your question regarding grounding on the reflector. Always make
sure you use proper Al to Cu joint compound. Al and Cu are "enemies" of
each other corrosion-wise. I tend to use copper strapping and brass as an
entrance panel, those are a lot closer galvanically, less corrosion. You
can usually get plate brass at a radiator repair shop. For copper to
brass, I use Cu joint compound, not the regular Penatrox/Noalox/etc. (grey
color). Always check the joint compound, as to what it is designed for,
before using.
Al to Cu can normally use a Penatrox type of joint compound. Make sure you
use that, and check the joints every few years...
Thickness of the copper strap is not that critical, but the wider it is,
the better. A wide strap but thin, will have less inductance than a thick
strap, but narrow. I use a minimum 2" copper strap for outside grounding,
and into the shack. In a small pipe, you can curl the copper strap to fit
the pipe, but never fold it, that adds a lot of inductance to it.
Use lightning arresters just outside the entrance, tied to your outside
perimeter ground around the shack. The idea is to stop any lightning before
it enters the shack.
73
Steve VE3RX
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