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 a 1967 Raytheon manual. The transistors are from the time. Equivalent modern...
This circuit was published in a 1979 magazine, but it can still be easily assembled as the...
The circuit presented generates short pulses. This configuration was found in a publication from...