Pentex production unit: B switch, 1965-1971
1965-1971
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
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
Hermetically sealed relay
Ferranti type FS relay
Ferranti model FR under current relay
Ferranti astatic voltage relay
Siemans Polarized Relay
1890
Ferranti capacitor control
AC Relay
Westinghouse bell-jar signalling relays from Glasgow Underground Railway
Polarised relay
Magnetic Relay as used in RAE RTV 1
Laws Relay as used in early RAE RTV 1
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
Relay, devised by Professor Wheatstone, c. 1838
1838
Siemens compound relay, 1876
1876
Relay, calling and clearing
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
Early pattern relay by A. Reyrolle and Co. Ltd.
1920-1950
Earth Leakage Relay
1940-1960
Ferranti astatic voltage relay
Type GF Telephone Relays
1915-1925
Wireless Telephone Relay
1915-1930
Telephone Relay
1925-1935
Telephone relay
1915-1925
Westinghouse bell-jar signalling relays from Glasgow Underground Railway
Single-element relay
