We found this circuit in Ferranti's 1974 transistor manual. The components are from the period. Note the relay type used.
This circuit was found in an Electronics World of 1969. Transistors are general-purpose types. It...
This control circuit for incandescent lamps was found in a publication from the 90s. The circuit uses...
This experimental circuit is from a 1975s publication. The coil consists of 80 turns of wire AWG...