Quote:
Originally Posted by jjmantele
Voltages for V2 (12AX7) Pins
1 _____146.8
2 _____0
3 _____1.2
6 _____182.7
7 _____2.9
8 _____44.2
AFAIK pin 7 is a red flag. The PI's grid is biased way cold. Cutoff? The bias is closer to ground instead of closer to the cathode. Maybe the 56k and 1500R to the cathode are flipped? Was this resolved? |
jjmantele,
Thanks, I took the amp apart and rebuilding it now for mostly service/cosmetic reasons. I will take a look at this when I power it up.
However, I was under impression that measuring grid voltage is somewhat problematic with a DMM so I disregarded it as most other people did.
Can you give me some hints as to how I should measure this voltage when I am ready?