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Jadis Orchestra bias adjustment

Hello,

Sorry to rehash this as I know it was discussed a few months ago.

I have my Jadis Orchestra opened up and am trying to find which resistor to measure across to set the bias to the recommended 110mV. A picture would be cool but even the resister value would point me in the right direction. I am measuring across the 5.62 ohm resistor connected between the anode of the EL34 and the output transformer and measure 86mV but I don't think that's the correct place - although perhaps this is an acceptable alternative?

If you are knowledgeable regarding this operation I'd really appreciate some direction.

Thanks so much!
Jim
jharmon

Showing 1 response by jharmon

jharmon OP
1 posts
 
Thanks so much for the reply!

Very interesting. Obviously the second DVM is there to compare the two output tubes to each other. I guess alternatively you could just set each to the required level but I get your method as a great way to ensure that, whatever the level, they are matched. Good show.

You are careful to point out which is the first and second pot. Is there significance in which one to use to adjust the initial level and which one to do the matching?

Thanks again. Good stuff.

Jim
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