Metal detector receiver (CB22457E)

Found at Popular Electronics this receiver is used with a transmitter for quadrature-coil signals.

Stereo balance indicator (CB8509E)
Found in a 90s Popular Electronics, this circuit uses a simple 9 V source. The power can be used...
Electronic injection (CB12933E)
Originally the circuit in the figure is indicated by National for the control of an electronic car injection...
Micro MW Receiver (CB16436E)
This simple receiver that works with only 1.5 V, was found in a 1987 documentation. The integrated...