The power transistor of this circuit can also be the TIP42 mounted on a good heat sink. The circuit is from old European documentation and the integrated circuit used is not very common today.
This circuit releases a lock only if the correct 4-digit sequence is entered. The circuit uses...
Found in a 1969 Electronics World, this circuit generates low frequency signals with two...
This setting appears with variations at various points on this site. This is from a Motorola...