Found in Electronics now from the 90s, this circuit uses a sensor from the time, which is difficult to find today. The circuit activates a sonalert-type buzzer.
This circuit was found in a 1965 General Electric documentation. SCRs and unijunction may be...
The BA1404 integrated circuit (not very easy to obtain) consists of a complete stereo FM...
This circuit is from a Radio Electronics documentation from July 1959. In this documentation the...