There are some high value resitors in that circuit and they tend to brcome higher values with the passages of time. After @dl324 suggestions, suspect high value resistors in the Z circuit.I've got a 50 year old Tektronix scope 454 where the Z axis barely works. The trace is visible when the intensity (brightness) is turned all the way up. Then a minute later, the trace fades away. Has anyone ever worked on the Z axis HV on a scope?
by Jake Hertz
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by Jake Hertz
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