This circuit, which controls both the temperature and the level of a liquid in a reservoir, was found in an Electronic Design from the 90s. The circuit is based on a double 555.
This circuit provides a small delay to a signal, being able to use transistors equivalent to the...
This circuit was obtained in a 1989 publication and is quite simple to assemble, but critical in...
This circuit was found in a 1977 documentation for radio amateurs. Integrated circuits are common...