This circuit fires with the noise captured by the touch of a sensor. Signal shapes are given next to the diagram. The circuit is from the 80s, using components from that time.
In the figure we have a TTL logic interfacing circuit as CMOS logic using a 6N139 optocoupler...
This regulator is based on the SFC2308 integrated circuit, which is quite old, therefore difficult to...
This oscillator that generates signals below the audible range (sub audio or infrasound) was found...