Quadrature detector (CB21753E)

This circuit was found in a 1977 American manual. The integrated circuit is from the time. Component values depend on the frequency range.

Photosensitive power circuit (CB25193E)
This circuit can be used in alarms by activating a relay or a current load that depends on the...
LM3900 Non-Inverter Comparator (CB14207E)
The circuit given below was found in the National Semiconductor Linear Applications Handbook. The...
Phototransistor Currente Control (3) (CB14641E)
The current of this circuit is determined by a PNP transistor. The circuit is suggested by Texas...