Found in a Popular Electronics from the 90's, this circuit can generate frequencies according to the values of the employed components, according to the table next to the diagram.
This circuit is from the time when seat belts were still being adopted. Obtained from a 1976...
This circuit for modeling was found in a 1980s documentation. The SCR can be the TIC106 and the...
This CMOS circuit was obtained in a 1980s documentation. The circuit has a 10-second time delay...