This circuit uses CMOS integrated circuits and can operate with CMOS logic from 3 to 15 V or TTL with 5 V power. The power is obtained from the circuit under analysis.
This circuit, found in a 1986 documentation, uses an optical sensor to count pulses and, in its...
This circuit, found in a 1997 publication, activates a lamp or a monitoring camera when the bell...
We found this circuit in an English publication in 1981. It can be improved by exchanging T1 for a...