Signal generator (CB21057E)

Found in Popular Electronics, this '90s circuit generates harmonic-rich signals for testing audio equipment.

Stepper Motor Control (CB13805E)
This configuration was found in a 1976 publication. The outputs of the logic circuits are applied to...
Frequency to voltage converter 555 (CB25990E)
With this circuit it is possible to measure frequencies up to about 500 kHz using a common...
Touch Action Switch (II) (CB146)
The very high-input impedance of the CMOS gate allows this kind of device to be used as a...