Ken,
Only suggestion is to save your money, don't buy
a balun. Wind a choke at the feed point out of the
coaxial feed line. It'll work fine, last a long time,
you'll still have some money in your pocket.
'Doc

"'Doc" wrote in message ...
Ken,
Only suggestion is to save your money, don't buy
a balun. Wind a choke at the feed point out of the
coaxial feed line. It'll work fine, last a long time,
you'll still have some money in your pocket.
'Doc

It's amazing the things one forgets in life......

Why didn't I think of that???

If I remember right, about 6-8 4" dia turns should do it....

Right?

Ken kg0wx

"Ken Bessler" wrote in message
...

"'Doc" wrote in message ...
Ken,
Only suggestion is to save your money, don't buy
a balun. Wind a choke at the feed point out of the
coaxial feed line. It'll work fine, last a long time,
you'll still have some money in your pocket.
'Doc

It's amazing the things one forgets in life......

Why didn't I think of that???

If I remember right, about 6-8 4" dia turns should do it....

Right?

Ken kg0wx



For the record I wrapped 6 turns of rg-8x in a 2-5/8"
diameter loop - I used a round glue bottle as a form,
applying superglue to the coax then drying it with
baking soda (cures superglue on contact).

I ended up with a real nice looking coil......

I also lengthened my antenna to 26'7" per leg (that
was all the spare wire I had on hand). The antenna
now resonates at 8 mhz exactly.

Question - if I trim the antenna for resonance on 40m,
will I loose efficiancy on 60m? I think yes but I could
be wrong - nobody's perfect.....

Except maybe Cecil...... ;-)

72's de Ken KG0WX

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

"'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

Ken,
Migration and solid dialectric insulation, sure, but
it all depends on the diameter of the coil. If you really
wrap the thing tight there's more chance than in a 'looser'
coil. Even in foam dialectric migration isn't a quick thing,
in the solid stuff, it's even slower but it does happen.
Don't count on much performance for your antenna on 160
meters. It may load like crazy, but that doesn't say how it's
efficiency/performance will be. Sort of like a 2" rubber duck
on 2 meters, it works, but not much. But, anything is better
than nothing!
The Century Club is a good place to test how an antenna
works,
lots of stations in all parts of the country. I used to 'live'
on the Century Club when I was working (slow shifts, kept me
from being bored to death).
Good luck with it!
'Doc