Diode Tester (CB22137E)

This diode tester was found in an English publication from the 1980s. Transistors are general-purpose types of the time.

TTL LED Driver (CB840E)
This circuit acts as a NOR gate for LED drive from TTL outputs. The circuit must be powered from a 5...
Integrator 741 (CB12990E)
In the figure we have the simple way to obtain an integrator with an operational amplifier of type...
Digital Speedometer (CB17306E)
This circuit, found in a 1986 documentation, uses an optical sensor to count pulses and, in its...