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mickeyd415
Hello everyone nice to be here. I have a question for anyone that might be able to help. I have a '65 Fender Twin Reverb Re-Issue and I am trying to bias this for the first time. LEt me explain what I have done and the numbers I have for intepretation. First I took the plate voltage of the amp. Tube 1- 451.4 Tube 2- 451.4 Tube 3- 448.2 Tube 4- 448.6 I got this by taking my DMM on end to ground the other to pin #3 on each power tube. Next I took the DMM and set it to Dc Millivolts and placed one lead on the board on the B+ line (Red) and placed one lead on the tube that had each side of the output transformer on it. On the brown side I got 36.01 mv on the blue side I got 33.86 millivolts. Now with all of these numbers what is the next step to determine what each tube is pulling and what do I need to adjust the bias to (I am using 6L6 GC's) Sorry this is so long for my first post but I sure would appreciate some help. I also hope I gave enough information. 