Model 19 - I think I took a wrong turn....

[Jamie Starr]

My issue with the bottom of the waveform clipping in my 19 was due to Q1208 as well, so I replaced both channels with an MPSA92 and then both channels clipped on the bottom side!

I found that slightly adjusting R1226 (load line adjust) brought both channels to perfection. They’ve been glued into place, but have been sitting in the same position for years. Maybe give them a little adjustment after marking them with a pen so you know the original position and see if that brings the boards to life.

Also, another thing that killed my audio was the time delay board. Make sure you have the 28v on 1204 and 26v on 1203. I only have about 8v on 1204 and 6v on 1203. I found that a zener had given up on the time delay board. I replaced it with a 1W 6.8V zener and it came back to life.

Dan

How did you access the time delay board? I bought the caps for it, but It looked so difficult to access, that I did not want to risk doing damaged. Thx.

 

[clinic-audio]

Sometime there is some gummy parts on the bottom side of the chassis (under the pcb) and with the age these gummy parts become like glue but you should pull on the board and that's it (if you have taking off all the screws and potentiometers nuts) !