Both the operational amplifier and the diodes admit equivalents in this circuit suggested by National Semiconductor. The power source must be symmetrical, and the circuit curve resembles an ideal diode.
This circuit was found in the January 1971 Radio Electronics magazine. It keeps the light flashing if...
This circuit is from the SGS manual of linear integrated circuits. The circuit can be implemented with...
Found in a 90s Hands On Electronics, this small preamp finds applications like microphones and other...