With distortion of less than 1 dB from 10 Hz to 20 kHz this circuit was found in the December 1972 issue of Radio Electronics magazine. The amplifier is a type that preceded the 741, the 709.
This circuit was obtained from an old American documentation having a limited adjustment range....
The movement of the LEDs in this circuit mimics the back-and-forth movement of a pendulum, making it...
This circuit is from a 1967 documentation. It makes use of varicap and diode tunnel in addition to...