I had a problem with my FT-1000D sticking in TX when keyed by CT from the
front panel jack with a keyer
"Y" connected. (10 and 20 M with more than 400-500 Watts.) I assumed it
was RF getting into CPU. Did all good things, no significant change.
Half way thru CQWW, a light lit up in my head - ground loop??? I unplugged
the shield part of the phone connector from the computer to the "Y" that
went to the keyer and FT1000, and the problem went completely away and
stayed away.
Needless to say, this would allow lots of RF into the cable to the FT1000
key jack, but it apparently eliminated RF current flowing on the shield
which was the real problem.
NO guarantee that this will work for anyone else, but, it is easy to try.
73 all, John, K1AE
>
>
> The CT LPT1 keying circuit can modified. Put .01 capacitors at the
> transistor's base to ground and at the transistor's emitter to ground.
> This solved my RF problem when 1500 watts output would key-down my rig on
> 20 meters with the beam at 330 deg.
> 73, de Joe - AA4NN
>
> On Thu, 2 Dec 1999 18:52:28 -0000 "Thomas Koglin"
> <thomas.koglin@planet-interkom.de> writes:
> >
> > >
> > >I see RF problems posted from time to time. Just wanted to pass along
> a
> > >tip. I have a Yaesu 1000D and I had RF drive me crazy at the
> beginning of
> > >the contest. Went through a lot of gyrations (toroids, other versions
> of
> > >CT, etc.) but the bottom line fix was to pull the keyer plug out of
> the
> > >front of the rig and leave only the CT keying plug in the back of the
> rig.
> > >Yes, I used shielded cable. Anything above 400 watts would lock the
> rig in
> > >xmit. I pulled the plug from the front and ran legal limit for the
> rest of
> > >the weekend. For what it's worth . . .
> > >
> > >Ron ND5S
> > Hello
> >
> > I´ve had the same problems with this rig, but only on 15m and pwr more
> than 500W.
> > I did not try the plug in the back - tnx for the tip - but have solved
> this> problems by using of some toroids in front as well.
> >
> > 73 de Tom
> > DL5LYM
> >
>
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>
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