I have replaced the back-to-back meter diodes on the Harbach diode meter board
(which came with the amp pre-installed, and is not the latest version),
replaced the capacitor block, installed a 10 ohm Ohmite glitch resistor,
reassembled the amp, and powered up for the first time.
Meter lights come on, fan comes on, tube filaments light up brightly. But the
meters remain stuck on zero. With the switch set to HV, both meters read zero.
I am not expecting to see grid/plate current, but I certainly expect to see a
solid HV reading.
I don't know if I have a meter problem, a resistor problem, or an actual lack
of HV. I am particularly concerned because it's difficult to know if the
capacitors are fully discharged before opening the case when you have no HV
meter reading. My guess is that it's either the meter(s) or a resistor/diode
problem (though I checked all the diodes on the meter board before
reassembling) rather than an HV problem. Is there any easy way to test this
with the power off?
I haven't tried to key up the relay or push RF through it.
Thoughts on next steps? I'm pretty confident the bleeder resistors will drain
the caps since all of the caps and resistors in the power supply section are
new. I am **not** particularly eager to do any work with the case open and the
240V power plugged in, much less powered up.
If anyone has a schematic for the metering circuit, not just the meter/diode
board but including the meters, that would be helpful. It's difficult to trace
circuits from the Heathkit pictorial manual without a schematic.
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