Fast adder 1 (CB7055E)

We found this circuit in an Electronic Engineering from the 90s. It applies to any logical family.

a Photodiode Amplifier with Trigger (CB4579E)
In the figure we have a sensor circuit that makes use of common transistors and a photo diode as...
Diode Coupled Multivibrator (CB19521E)
This unusual configuration, but which has already been explored in other articles, uses diodes in the...
Proximity Switch 567 (CB15008E)
This circuit uses a modulated signal from a PLL 567 to operate safely with an infrared emitter. The...