This circuit uses a feedback integrator. We found it in Ferranti's transistor manual from 1974. Transistors are general-purpose types at the time.
This metronome was found in a 1979 publication, but it can be assembled more easily with the BC548...
Wired to the output of any amplifier this circuit makes an incandescent lamp flash according the...
This type of circuit, even with the same configuration, appears several times on this site. The...