Found in a 90s Popular Electronics, this circuit interfaces the telephone line with an audio amplifier, reducing impedance matching and noise problems.
This circuit makes use of a mechanical delay line to produce the reverberation effect. This is a...
This circuit was found in an American documentation from 1975. The components of the time can no...
The oscillator circuit is an ICM7556, the dual CMOS version of the 555. The frequency depends on...