Tachometer, Victometer Centrifugal, 1920s USSR such as the B-17 Flying

such as the B-17 Flying Fortress (see image illustrating the location of the co-pilot's regulator from the B-17F flight manual dated 1943)

receiving ground signal from a selected transmitter via its loop antenna mounted top or bottom of the fuselage (see photo of an example of the loop antenna)

The knob was used to set the flow rate

the electrical connector is protected by a removable metal cap

The glass is intact

Tachometer, Victometer Centrifugal, 1920s USSR such as the B-17 FlyingThis is a WWI or Post WWI vintage aircraft or laboratory tachometer "Victometer" made by the Jos W Jones Co. This is a centrifugal tachometer: as the rotation of the engine shaft rotates a cable attached to the case, flyweights rotate around an internal axis. The weights move outwardly due to centrifugal force, which pull a brace attached to the spring loaded pointer. As the brace is pulled by the centrifugal force of the weights, the pointer is