Found in American documentation from 1969, this circuit uses logic inverters to obtain sequences of 4 pulses. The circuit can be used as a shield.
This project is from a 1982 documentation, based on an astable multivibrator with two transistors. The...
Found in ancient American documentation, this circuit uses some components from the time, such as...
We found this circuit in an old publication. The circuit can be implemented with modern equivalent...