"'Doc" wrote in message ...
Ken,
With RG-8 size coax I'd make the diameter of the coils
larger than 2 - 4 inches. A small diameter can make the
center conductor migrate to the 'outside' of the coil and
eventually short out (may take awhile). Something like a
3 pound coffe can makes a good form for RG-8. If you have
to force the bend, the diameter is too small.
If you tune the antenna for 40 meters it won't work as
well on 60 meters. The difference may not be all that much
though. I'd make it resonant on whichever band I planned
to use the most, and then 'put up' with it's performance on
other bands.
Something else you might consider. Extend the antenna the
rest of the way around the building and make it into a loop.
That should give you 80 meters and maybe even 160 meters...
'Doc

Thanks for the good info, Doc!

I made the coil 2-5/8" in diameter after trying to make the coil
on a coffee can and had problems with the lip and ribs of the
can preventing me from removing the finished coil. BTW the
2-5/8" is measured from the center of the coax.

Later I went to rat shack and bought 50' of 2 conductor
speaker wire, cut 10 feet off then added the 40 foot pieces
to my inverted V. It now measures 133'2" long and resonates
at 2.715 mhz. my new little Z11 tuner can easily take it down
the rest of the way to 1.800. If I wanted to I could add more
wire and go completly around the building, ending up with
a 200' loop (guestimate)

For the first time in my ham life I've got a 160 meter cap-
able antenna! I'm looking forward to winter.....

As I'm writing this I'm listening to the 3905 Century Club
net on 40 meters. Man - net control and others are booming
in here!

Also, is conductor migration really an issue with solid
dielectric coax?

72's de Ken KG0WX