This circuit was found in American documentation from the 1960s. The operational amplifier is from that time, but the configuration applies to modern equivalents.
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...