New "garbage can" Express build, all found stuff from my "workshop" area.
My B+ rail voltages for the PI and Preamp are spot on 318, 291, 281.
Preamp voltages for V1 and V2 are basically the same as on the Express Voltage Chart.
The PI is a little different:
V3A voltages
1-195
2-33
3-35
6-218
7-33.8
8-35
The amp sounds pretty good, wondering how to get the grid to cathode voltages farther apart?
What could be causing them to be that close to each other. I am assuming it is a question of biasing the tube differently.
I am getting dc voltage on the output side of the .1uf capacitors, 33vdc on the top .1uf coupling cap, .1uf feeding Presence control is 10vdc (that seems right).
I have a 10k tail and 470R currently in the PI.
To recap:
I just want to know why I am not seeing the 15 - 20 vdc difference between the Phase Inverter grid and cathode as on the "official" Express voltage chart.
Thanks for any help.
Express PI voltages off
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