Hickok 209A VTVM Restoration Part 1
This is the first installment in a multi-part series documenting my restoration of a classic Hickok 209A VTVM. First a description and some images:
This is a Vacuum Tube VoltMeter (VTVM) with a nominal 12 Mohm input impedance and one of the largest mechanical meter movements found on commerical/consumer equipment (viewing area about 8.5 inches diagonal). It was produced from about 1947 (earliest direct evidence) to at least 1961 (catalog reference). One of the units I have has 03-09-55 written in grease pencil on the back of the meter movement. The cost in 1947 was (reportedly) $133 USD which is about $1500 USD in late 2018. In comparison, the HP 410A (a lab grade instrument) sold for $245 USD in 1948 or about $2500 USD in late 2016 dollars. So the Hickok 209A was not aimed at the laboratory or R&D market, but rather at the service/repair depot market.
There seem to be at least two color schemes for this meter: Black front panel with a black meter face and white front panel with with a white meter face.
The serial numbers I have seen are:
- 1333254 (Stamped metal plate)
- 13310406 (Stamped metal plate)
- Unreadable (Decal)
In Part 2 I will begin the restoration process with a visual inspection. Thanks for reading.