I've completed at least the initial resurrection of a long dormant, and
neglected (abused?) 425, and have a question re what the resting current
(keyed, no signal) of healthy 3CX800's should be in a 425. With 2600v on the
plates, I'm reading about 8ma grid current, and 30ma plate current. These are
"interpolated" values from the panel meters, so anything but precise, and I've
not yet checked calibration/accuracy of the panel meter grid and plate currents.
Resurrection required re-attaching wires pulled from the ps rectifier board
(solder failures), re-flowing all of the fractured solder connections on the ps
J2 connector, replacing the blown 1-1/2 amp slo-blo F3 with the proper 4 amp
slo-blo, replacing the burned original plate choke with the Ameritron/MFJ
choke, installing the ball bearing in the rear of the "LOAD" capacitor shaft,
and of course general cleaning. My word! Wonder what the original owner's first
clue was that there might have been a problem. Smoke from the plate choke?
Haven't yet attempted actually loading the 425...just "burning in" the
long-dormant 3CX800's (I know...but old habits die hard). So, any estimates or
"swags" of what reasonable resting currents might be would be appreciated.
Tnx es 73,
Allen--W7GIF
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