This circuit was designed to power the previous circuits of the wireless sound system, but it can be used for other purposes. The circuit is from a Radio Electronics from August 1988.
This sophisticated logic probe for 5 to 12 V circuits (CMOS and TTL) was found in a 1980s...
EDN magazine in a 90's issue published this TTL technology debouncer flip flop circuit, in this...
This circuit is from Motorola's 1990 Linear Databook. The transistors allow equivalents and the...