I would like to echo Scott's appreciation for the radial wire discussion on
the reflector.
I am in the process of laying out a very large ground system for an array
essentially the same as described by John, W1FV, although mechanically
different. In my case I am not using any elevated radials but laying them
all on the ground. Three elements translates to a lot of wire (25k'+), with
a lot of connections where the radial fans for the individual elements
intersect. It is clear that regular solder for the multitude of connections
just won't fly so Don and Doug's suggestions are very helpful.
I had considered using aluminum wire for cost reasons and did some
experiments. A couple of years ago I buried samples of wire and also just
laid some on the ground surface which is grass covered. After two years the
surface wire is fine but the buried stuff is beginning to show some signs of
deterioration, not fatal but not good for the long term. I also attacked
the problem of making reliable, long term connections with aluminum wire.
After trying all kinds of solders that didn't work worth a damn, I found an
aluminum brazing rod, Al-Cu-Zn alloy, which seems to do a good job of making
wire-to-wire and wire-to-rod connections. You have to following the
instructions carefully and practice a bit to get this stuff to work but it
does a good job and seems to be highly corrosion resistant, at least in my
climate. After my solder experience I was very skeptical but this rod does
seem to work and can be done with a propane torch. I got the rod from:
Ideal Industrial Supplies Inc.
2005 Van Epps Road SE
Olympia, WA 98501
(206) 351-3471
Despite having an apparent solution to the aluminum joint problem, I think I
will stick with insulated copper and try the MAPP gas-brazing approach. It
will be a bit time consuming but should give a long term solution. In any
case I have to get up on my hill and get with laying radials! Winter is
coming.
73, Rudy N6LF
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