This circuit was found in a 1965 General Electric documentation. SCRs and unijunction may be current equivalents. The circuit has period adjustment and symmetry.
Found in Popular Electronics this circuit will trigger a buzzer if the ignition key is removed...
This circuit is from an English publication from 1973, but can be easily assembled today. 2N718 can...
The figure shows how to connect a relay to obtain the latch effect. The circuit is from an...