wrote in message
ups.com...

Hi Ken, I have had that problem with Auto tuners myself, and could not
get a satisfactory solution. The Vendors solution is Ferrite on the
coax, and make sure you have a good RF ground at the tuner.
The problem is almost certainly RF feedback getting into the tuner.
Since you have elimated current on the shield of the coax by the Radio
Shack cores (they should work, don't know of any recent studies of
these cores on 10m) that is not the problem.
The problem may be RF potential at the tuner by direct radiation. To
eliminate this you need a very good RF ground directly at the tuner.
For 10M this is a very short connection to a good earth ground. A 20'
long ground connection is not the answer.
You might try hooking a fan 10m dipole in parallel with the 40m
dipole. This would provide a better match for the Auto Tuner. If the
problem is still there, then it is direct radiation. Better RF ground,
or reduce power.
Gary N4AST

================================================== =========
Thanks, Gary.

I messed around with different chokes on different positions
until I had eliminated 90% of the problem. One of the biggest
helps was putting both a snap on square choke *and* a coaxial
choke right at the back of the rig where the HF coax attaches.

I used 2 standards - I had my son listen on the computer with
headphones and rate the FM buzz from 1 to 100. We started
at 75 and ended up at 2. I also switched from 20m to 10m and
kept track on what power level would cause problems on trying
to tune 10m. I started with 65 watts and ended with 95 watts.

I have a Cuscraft R7000 that KB0OMQ gave (!!) me - when
I get that up, I imagine my problems will be solved, at least as
far as trying to get my 40m antenna to load on 10m

--
73's es gd dx de Ken KGØWX
Grid EM17ip, Flying Pigs #1055,
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