This two-microphone amplifier was found in a April 1961 Radio Electronics Magazine. The circuit is powered by battery and has a 600-ohm line output.
Found in a 1968 Mullard manual, this circuit measures temperature by infrared radiation. The...
Found in a 1970s RCA documentation, this circuit generates signals according to the component...
This Harris circuit from the 90's is intended for recording old EPROM memories. The circuit uses...