I have a VTVM that works but scale is way off. 12 volts dc reads 3 volts, 120 volts ac reads 20 volts, and resistance cannot even get meter to go to infinity or 0 when touching probes together. When turning unit on meter neadle deflect all the way to right then returns to left and you can get 0 adjustment on dc and ac, so what ever is wrong seems to be affecting all ranges and functions. My belief is that it must be a resistor between tube 12au7 and power supply any thought?
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