On Sun, 11 May 1997 19:05:17 EDT ko4a3@juno.com (H. J. Kohl) writes:
>Help,
> The grid current meter on my SB220 is all the way to the right
>with key down, even on SSB mode of the exciter. On dekey the meter
>pegs the left side. Is this a tube problem or meter circuit problem.
> Suggestions please.
>
> Thanks,
> John
> KO4A@juno.com
The SSB position will worsen whatever the situation John, run the tests
in the CW position with no drive when keying the relay.
A few things to check:
1. the Zener diode
2. the .82 Ohm grid metering resistor
3. One tube at a time
Before doing anything put a back to pack pair of diodes across the meter
terminals. Any 1N4nnn series will be fine. At least the meter will be
saved if something nasty happens.
If those 3 basic steps check out OK, get back to me and I'll work along
with you.
73....Carl KM1H
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