This circuit has a sensitivity of 2uW. We found it in documentation from the 1980s. The integrated circuit is from that time. Equivalents can be tried.
This circuit for old platinum cars was found in a 1967 Motorola documentation. The power...
This egg timer has been found in an English magazine that no longer exists in 1982. The...
This circuit is from an old Signetics documentation. It can be implemented with modern operational...