Signedon base between the binding posts in raised letters: LEEDS & NORTHRUP CO. / PHILADELPHIA PA
Inscribedon base, front: (serial number): 235287; moulded flap swings out from underneath the base with the meter's specifications (see Card); on case, top: MADE IN U.S.A.
FunctionReflecting galvanometers are used to measure very small electrical currents and voltage differences. Instead of having a scale with a pointer, in these galvanometers a small mirror turns in the presence of electrical currents. The change of angle can be detected by shining a light at the mirror and observing the reflection on a large scale that is placed in front of the device. Alternatively, a scope is pointed at the mirror to see the change in the angle that the scope points to on a scale seen through the mirror. In those cases, the scales that are used are mirror-inverted.
Provenancefrom Jefferson Laboratory (Harvard University), 04/27/1970.