TF1041C Vacuum Tube Voltmeter

The TF1041C measures DC voltage, AC voltage and DC resistance. The AC input is via a probe with a built-in valve diode detector, allegedly making it possible to measure voltages to frequencies over 1 GHz.

This one is probably from the 1960s. The TF1041 series was superseded by the later TF2604 which, although presented in the more modern 1970s style case, used very similar circuitry.

It isn't working so is a project for "when I get round to it" time.

There are some circuit diagrams in the zip file below.