We found this circuit in an American publication from 1977. The circuit drives two LEDs according to the control of the inputs. The technology is TTL requiring 5 V to power supply.
The operational amplifier used in this application is not the most common today. The circuit is...
This basic blocking oscillator configuration was obtained from a 1954 transistor book. The...
This circuit appears elsewhere on this site, but from different sources. Using the LM3900, we find this...