In the original publication of the 90s a 556 consisting of a double 555 is suggested. The circuit drives a speaker with good power. The power transistor shall be fitted with a heat sink.
This circuit triggers a reed relay from an input voltage. The circuit is from a 1980 publication and the...
This circuit using a SIDAC as a relaxation oscillator was found in the ON Semiconductor manual for...
This transistor flasher was found in an English magazine that no longer exists from 1975. The...