04-24-2022, 06:14 PM
I misunderstood the adjustment you were describing. I was thinking electronic and you were thinking mechanical. I found the manual for it: http://www.mcmlv.org/Archive/TestEquipment/HP400.pdf Seems likely that the issue might may be CR-1 and 2. These are the diodes are connected the meter. After all the yrs they may have developed some leakage causing the needle to favor one side or the other. Might not hurt to replace the two 2mf caps too.
When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!
Terry