Pentex production unit: B switch, 1965-1971
1965-1971
Hermetically sealed relay
Westinghouse bell-jar signalling relays from Glasgow Underground Railway
Polarised relay
Telegraph relay (1920s)
1920-1930
Western Union polar relay 17B, dated 14.12.1915
1915
Western Union combination Wheatstone relay
1915
Telegraph relay (1920's)
1920-1930
Telephone relay by S. G. Brown
Original Swedish "Birka" bimetal relay with heating coil
Slow acting relay
Dash-pot relay, for timing delays (1920's)
1920-1930
Overcurrent relay by Reyrolle, no. 142568
G.P.O type 600 relay
G.P.O. type 3000 relay
Ferranti type FS relay
Ferranti model FR under current relay
Ferranti capacitor control
Ferranti astatic voltage relay
Siemans Polarized Relay
1890
AC Relay
Non-polarised relay
Siemens high speed relay with dust cover
Single point telephone relay 1908
1908
Relay by ATM, 1915
1915
General Post Office Type B landline telegraph relay capable of regeneration
1880-1920
Relay 556
744 relay no. 594
Relay, local Murray auto 2/2
Gulstad vibrating relay
Allan and Brown relay
Wireless Telephone Relay
1915-1930
Telephone Relay
1925-1935
Telephone relay
1915-1925
AC Relay; Model 2A
Relay, devised by Professor Wheatstone, c. 1838
1838
Early pattern relay by A. Reyrolle and Co. Ltd.
1920-1950
Siemens compound relay, 1876
1876
German "Birka" thermo-electric "wire-type" (no bimetal) relay in vacuum tube
Miniature microphone relay
American 2 pole relay
G.P.O. type 3000 relay
Type GF Telephone Relays
1915-1925
Single-element relay
Relay, calling and clearing
Westinghouse bell-jar signalling relays from Glasgow Underground Railway
Westinghouse bell-jar signalling relays from Glasgow Underground Railway
Magnetic Relay as used in RAE RTV 1
Laws Relay as used in early RAE RTV 1
Earth Leakage Relay
1940-1960