Line voltage: 120
Voltage across pins 4/6 of rectifier: 716vac
B+ at pin 8 of 5AR4: 416.0 vdc
B+ at pin 8 of 5Y3: 411.3 vdc
In summary, about a 5vdc drop in B+ using the 5V3.
I'll measure on an ST120 soon.
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