A friend of mine gave me a old Tektronix 422 oscilloscope, the problem is channel "2" does not work. I can see the trace off the screen,and i can bring it up onto the screen by using the variable calibrate knob on channel two, but the calibration is way off.. Someone had mentioned that the "Nuvistor" tube that controls the vertical amp was most likely gone bad, which was common for this model. When I opened up the scope, I could not find any tubes anywhere inside. I later found out that the later model 422 scopes discontinued to use these "nuvistor" tubes and switched to use a "FET" instead. I can not find any schematics for this scope on the net that uses a FET instead of this tube.
If anyone knows where i find this information or what FET number they used for the vertical amp I would really appreciate it.
Curtis