Great suggestion Tom! There is a diode on that leg I do suspect.
I'll remove one leg of it and check it out today.
Thanks & 73,
Brian
On 11/1/06, Tom W8JI <w8ji@w8ji.com> wrote:
> > The HV came back after replacing the resistor, however now
> > my grid
> > current goes way high. Even keying the amp with no audio
> > on SSB shows
> > about 15 to 20 mils of grid current.
> >
> > When I applied some excitation (maybe 5-10 watts), it did
> > indicate
> > output and plate current, however not knowing if the meter
> > was reading
> > correct or not, I did not take much time to measure actual
> > output for
> > fear of losing the grid. With 20 to 40 watts of drive,
> > the grid
> > reading nearly goes off scale with no effect turning the
> > load cap.
> > SWR is 1:1, so no problem there.
>
> Brian,
>
> That is almost always a short from the negative rail of the
> HV to ground at the filter capacitor side of the metering
> circuit.
> What that will do is place the grid meter in parallel with
> the plate current meter.
>
> Look for a diode that goes from the chassis to the negative
> rail. It is normally a conventional rectifier diode,
> although it could be a low voltage zener.
>
> 73 Tom
>
>
>
--
"There is nothing more uncommon than common sense." -- Frank Lloyd Wright
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