• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Looking to repair a Feiler TS-9 Electronic Vacuum tube Volt-Ohm-Milliammeter

I know that several have mentioned that better accuracy can be had with a digital meter and they are correct. I wanted a vacuum tube meter when working on old radios as they do not drag down the circuits when trying to peak a radio. Anyway the vacuum tube Eico 221's that I have restored and this Feiler is close to my age and to be honest it makes me feel good to be able to use a piece of history.

The Eico 221's are within about 4% for accuracy and the Feiler is at 2% which isn't bad for meters of this age. I did however update the unit with a battery eliminator circuit which eliminates two D cells in the Feiler.

My impressions.. the Feiler is more accurate and a more complex circuit, more tubes, and more wiring and yes I know not as accurate as say a new Fluke.

Sorry for the hand drawn circuit well mostly I did borrow part from the Eico, If I had a cad program I would have drawn a decent schematic but at least this may serve to help someone in the future if they stumble across one of these rare units.
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