This circuit is from 1975 documentation. Transistors such as 2N3055 can be used and the transformer is of a special type. R1 is 200 ohms and R2 is 10 ohms.
This circuit was found in a 1989 documentation. The output must be applied to a power step for...
Found in a 1980s Electronics Now, this circuit uses common components. Transistors are commonly...
This circuit activates a piezoelectric buzzer with an oscillator at the end of the programmed...