Re: Marconi Valve Voltmeter TF1041C - repair thread
Replaced remaining caps and but no further improvements made.
It now reads with about +1v DC offset on the 30v to 300mV ranges
But I don't detect any offset on the 1000v to 100V ranges.
The source of the offset must be quite high impedance, my fingers across the probe tip and ground can almost kill it.
The probe tip has about +100mV DC on it in the 30v to 300mV ranges.
But virtually nothing on the tip in the 1000v to 100V ranges.
so I reckon this tip voltage is part of the problem.
Note, when connected to any voltage source it reads the voltage very accurately in all ranges.
If anyone has one of these, could you possibly test the tip voltage in DC and let me know what it reads?
Thanks
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Regards
Ray
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