This circuit of the 70's uses transistors of the time. The circuit can amplify signals from 10 Hz to 100 kHz and modern equivalent components can be used. The circuit is from Ferranti.
In a voltage follower, the gain is unitary, and the input impedance is very high. The output...
This circuit, from an old 1988 publication, generates bars on the screen of an old analog TV for...
This circuit is from a Motorola integrated circuit manual. The integrated used is no longer common...