This circuit is used in a LASER detection system to avoid echoes from short distances in systems up to 1 mile. The circuit is from a 1967 documentation.
This circuit is from 1985 documentation. The integrated circuit is not very common today, but...
This power supply is protected from shorts in the load. The BD135 must be mounted on a heatsink...
This receiver for the police band, which at the time was 45 MHz, was found in a publication by...