[skajohyros]

Not my diagram. Just used it for my build as it was pretty straightforward for a beginner.
Have a good day.

 

[tomb]

Good to see you're still around Tomb. Bear with me as I'm almost clueless.

I'm using the 12au7 layout. Pin 4 is connected to source. What should be the voltage readings here?
Also, non grounded ends of R4,R10 are about 14v.
Are my original MOSFET readings ok?
I'm confused.
Basically, where should I be checking for voltages and resistance and what are the expected values?
Cheers.

Pin 4 should read about 12VDC, which should be the heater voltage across tube pins 4 and 5 (Ground). However, "12VDC" is an estimate based on the Dsavitsk-The-Equalizer mod for the 12AU7. You may not get that voltage, depending on the resistors selected and their tolerances. If it's higher, it's possible you've burned the tubes out prematurely.

To review, with the 12AU7 mod, resistors R2 and R8 should be 390K. If less than that, you may get a much higher voltage across the tube heaters. R2 is in parallel with R3 and R4, so you'd probably need to verify the resistance from your records or the code on the resistor. You probably won't get a good reading from the DMM while the resistor is in the circuit.

Pin 4 should read the voltage to ground of the heater supply voltage. That is also the MOSFET Source voltage. Your earlier post showed measurements of 22VDC and 14.5VDC. The 14.5VDC checks out with the ~14VDC you're saying you measured at R4 and R10. The 22VDC is an anomaly. If accurate, it probably means the tube heaters in that tube could be burned out. The thing to check here is what is the voltage across pins 4 and 5 for the tube that measured 22VDC at pin 4? It would also be helpful to swap the tubes and see if the 22VDC changed to the other position. That's a quick way of telling you the problem is in the tubes.