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Hey all, long time no talk but I'm finally finishing up the amps and hope to have the up and running by Sunday.

I'm using the 12BH7 for the V2 positon and am currently getting around 312VDC. Is the correction for the long tail pair plate resistors (R10,R11) for the 12AU7 apply for the 12BH7 or should I keep the 47K resistors in place? Ned's manual still shows the 47K resistors.

What is a CCS set resistor? Would that be R9?

Also, is there a reason I'm getting 16V instead of 10V on pin 3 of V2? All my 6.3VAC points are at 6.9VAC. Could this be because of my consistant 127-128VAC line Voltage? I've got origanal Dynaco Iron.

Ty set me a schematic for making buck booster like transformers to tame the line voltage http://www.geofex.com/Article_Folders/v ... ntvolt.htm (Thanks Ty). I like the idea of selecting between -6 and -12V. I've ordered the transformers from radio shack so I hope to see what this does to my Voltage chart!

Thanks,

Jason

Yes, R9 is the constant current sink set resistor.
The 47k plate resistors should be ok for a 12BH7.
The 10 ohm set resistor sets the current at about 7 ma depending on the temp. Looking at the 12BH7a curves with 312 volts and 7 ma , 16 volts on the cathodes is right on the money so don't worry.