I had similar problem with mine. It seems that the Control position pot Controls many of the functions of the CPU. (even seems to affect the operating buttons and even can affect the meters). They all connect to IC8. Try marking your high and low pot presets positions, and then adjust them a little in each direction to see if that helps your problem. On my had to turn the low pot a little bit to the right(from the front of the unit) to make it work properly. Also, my operation pulley ended up not being straight up, but a little bit tilted to the left (from the back of the unit, )by about 5 degrees. My low voltage is .77v and my high is 6.1 v. Which is different from the Service manual. I don’t know if this will help on your unit, but it’s worth a try. Good luck I hope this helps
I had similar problem with mine. It seems that the Control position pot Controls many of the functions of the CPU. (even seems to affect the operating buttons and even can affect the meters). They all connect to IC8.
Try marking your high and low pot presets positions, and then adjust them a little in each direction to see if that helps your problem. On my had to turn the low pot a little bit to the right(from the front of the unit)
to make it work properly. Also, my operation pulley ended up not being straight up, but a little bit tilted to the left (from the back of the unit, )by about 5 degrees. My low voltage is .77v and my high is 6.1 v. Which is different from the Service manual. I don’t know if this will help on your unit, but it’s worth a try.
Good luck I hope this helps
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