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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
dischief
kentaja
25 posts
 
Biasing any of the VT series amps is a snap. The instructions clearly state the procedure and the resistors, 2 per channel as I recall, where the readings are made are on the top of the PCB right under the top cover. No need to dig around inside to find the resistors. The resistors/test points are clearly identified on the board. Can't get much easier than that.

I understand the caution and concern but no need to make a simple procedure difficult.
rrog
1,958 posts
 
Kentaja gives good advice. If you think the VT series is hard to bias you should try one of their older amps.
jea48
4,425 posts
 
Dischief,

Not sure about the VT200 but the biasing of a VT100 mark 1&2 can be a bear if changing the small signal tubes along with the power tubes.If done improperly the new tubes and or the amp could be damaged.

My understanding changing the power tubes only is some what simple....

You might want to give ARC a call and find out if the VT200 bias like the VT100 mark 1&2.

http://mycollins.net/audio/artube1.html
http://mycollins.net/audio/artube1.html
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