This circuit can be used as an answering password system in a store, office, or other location. The circuit is from Intersil using components of the time. The circuit is from the 80's.
Other series amplifiers such as the MC3301, MC3401 and LM2900 can be used on this circuit. We...
This configuration, widely used in our articles and on this website, uses a 555 to control a relay...
This circuit was found in an English documentation from the 90s. It uses a PLL CMOS 4046 and is...