In the figure we have a way of receiving ultrasonic signals of a single frequency using a PLL 567. The circuit is from Radio Electronics from November 1985.
This circuit is from Radio Electronics from March 1977. The integrated circuit is from that time...
This 1.2 to 32 V x 3 A regulator was found in an 80's EDN. The power components must be equipped...
This power control from Motorola's 1971 SCR Power Control Fudamentals can control full wave loads...