This circuit for audio signals was found in the March 1990 Radio Electronics magazine. The circuit uses a unusual optocoupler that can be replaced with an equivalent one.
This 80's circuit uses an integrated amplifier of the era, but nothing prevents it from being...
This power supply was found in a RCA publication from the 1970s. The circuit uses transistors from that...
Maxim MAXREFDES67 Universal Analog Input Micro PLC is ideal in factory automation because of its...