Found in a Philips publication from the 1970s, this circuit uses a DO040, which is difficult to obtain today. The circuit is powered by 12 V on pins indicated in the diagram.
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...