This simple logic test circuit with 3 LEDs was found in October 1985 Radio Electronics magazine. The power supply is according to the logic, and this version is indicated for TTL.
In fact, we can say that this circuit found in documentation from the 90s, consists of an intercom...
The basic integrated circuits of this 1988 multimeter are no longer very common today, but if...
This circuit is from an old publication of the 70's. It can be implemented with modern transistors like the...