ID:
2557
Maker's Name:
Weston Electrical Instrument Corp, Newark, N.J.
Where made:
USA
1938
Dimensions:
34 × 24 × 10.2 cm
Units such as these were used by repair technicians to test whether valves (vacuum tubes) were working to specification.
Valves had only short operating lives compared with other components and plugged into sockets so that they could be swapped rapidly.
The case is Bakelite and has space for batteries (3 x size C) for the cathode heaters, but external supplies were needed for anode voltages.
