Contact Key – Morse Code Key

Used for measurement of small quantities of electrical charge.

Levelling Screws for balancing the coil. Coil with mirror suspended between long suspension at the upper end and a spring at lower end. Suspension and spring are made of phosphor bronze alloy. Bakelite case, rigid and robust. Clamping arrangement for transportation. Consistent sensitivity over a large period. Strip provided for making it a periodic

A contact arm & three metal studs mounted on a bakelite base with three brass terminals. The centre terminal is common connection to the arm & the other two terminals connected to the other studs.