This circuit is from a 1976 Motorola CMOS manual. It can be implemented with modern Darlingtons like those in the Texas TIP series. The load current depends only on the Darlington transistor.
The presented circuit is a sinusoidal oscillator for 1 kHz that makes use of the four amplifiers...
This headphone amplifier has good gain and high input impedance. The circuit is from Electronics Now and...
Based on the 4006 this circuit generates random signals in a frequency range that depends on L1...