Audio Research VTM-200 Bias Issue


I’m working on a Audio Research VTM-200. Currently all of the tubes power on but all of the bias’s read 0 on the back and no volume to the speaker. I’ve seen this behavior with other amplifiers when a fuse is blown preventing the tubes from biasing up. Is anyone familiar with this issue?

I read through the manual and saw there are 3 fuses per amplifier and I’ve located two, both of which are OK. I’m assuming the 3rd fuse needs to be replaced but I’m unable to locate it. Any assistance here would be appreciated!

On a side note, what do the bias numbers mean. If i see a reading of 65 is that 650mv?



F1, 7 amp

F2, 4 amp

Both located in AC power line.

F3, 1/4 amp

Scroll down the page until you come to the power transformer diagram. Start to scroll up keeping your eyes to the far left hand side of the page.

You will see 4 dual section caps with dotted line rectangles boxes around them. Just pass the caps you will see the F3,  1/4 amp fuse.


wiring schematic