MIRROR GALANOMETER BY H.TINSLEY, 1960's

Mirror Galvanometer made by H. Tinsley. A mirror is fixed to an armature and hung on a gold thread between an electromagnet, the mirror moves according to current in the coil. A light is reflected off the mirror onto a distant scale amplifying the reading. Used for measuring small electrical currents this was the most sensitive means of measuring currents during the early years of electronics. Galvanometers were used by the Post Office Telegraphy departments for detecting signals over very long lines.

See Item A0913 below where one is being used with a viewing screen.

A1613