10-13-2019, 12:30 PM
Hi Joe and welcome,
I'll add a few notes to the voltage readings. They may be somewhat higher (10-20%) as the higher line voltages and the meters used in those days had a low input resistance which would tend to cause a drop in the voltage being measured. Now days meters are 1Meg or much higher.
Should see abt -20dc on pin 5 of the 42 and a couple of -volts on the cap of the 75.
Don't think having the volume control full up is necessary. Shouldn't change the voltage reading just makes servicing more annoying.
I'm assuming that you've replaced the caps, if not do so unless you like chasing your tail!
GL
I'll add a few notes to the voltage readings. They may be somewhat higher (10-20%) as the higher line voltages and the meters used in those days had a low input resistance which would tend to cause a drop in the voltage being measured. Now days meters are 1Meg or much higher.
Should see abt -20dc on pin 5 of the 42 and a couple of -volts on the cap of the 75.
Don't think having the volume control full up is necessary. Shouldn't change the voltage reading just makes servicing more annoying.
I'm assuming that you've replaced the caps, if not do so unless you like chasing your tail!
GL
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
