This type of logic is no longer used today. The circuit is from an old American publication and the integrated circuit is uncommon today. Diodes are general-purpose tpes.
This configuration similar to many of this site was found in 1965 General Electric documentation. Modern...
In the figure we have the configuration of a logic switch with the TTL 7400 circuit. The...
This telegraph microtransmitter for a frequency determined by the coil and the crystal was found...