01-21-2012, 08:37 PM
Hi Mark,
I think your problem is that the 7Z4 is rated at 650 p to p vac. what you could do is remove the input cap in the power supply. This will change it to a choke input supply. This will lower the output voltage The 7Z4 is rated at 900vac choke input @120ma. Up the value of the other filters to reduce the hum. You could try adding a small value cap in place of the large input cap. Maybe like a .1mfd 630v. I'd try to keep it lower than 1mfd.
Have fun with it!!!
Terry
I think your problem is that the 7Z4 is rated at 650 p to p vac. what you could do is remove the input cap in the power supply. This will change it to a choke input supply. This will lower the output voltage The 7Z4 is rated at 900vac choke input @120ma. Up the value of the other filters to reduce the hum. You could try adding a small value cap in place of the large input cap. Maybe like a .1mfd 630v. I'd try to keep it lower than 1mfd.
Have fun with it!!!
Terry
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
