Biasing the small signal tubes is not as bad as it seems. The process is a bit finaky until you get comfortable with it, but I can do mine in about 15 mins with a single digital volt meter. The trick is to check the 60v rail voltages, and switch 2 tubes around at a time to get them as close as possible. This will make the lower mAmp adjustments easier whilst keeping the 60v rails even on the upper and lower traces. Albert does a good job of describing the process on the link. The ouptut tube bias is really easy, but keep in mind there is over 400v at this resistor!
Audio Research VT200 Biasing Schematic ETC.
Since Audio Research Corp. will not provide a PCB schematic for the biasing of my VT200 behemoth I would request anyone with a circuit board scan and/or schematic to come forward. I hesitate to do this with merely their 2 page biasing instructions as I also know any tech, even at ARC, would rely on a detailed image of the printed circuit board, component values, test points and detailed procedure.
Thanks,
John
Thanks,
John