Two-Tone Audio Generator (T326E)

This 1965 circuit generates 250 to 2,000 Hz tones with quality sine waveform. The power supply is not given and the tubes are of well known types.

Ultrasonic Oscillator (NI008E)
The 50 kHz signal generated by this circuit is applied to a low impedance inductive transducer. A...
Amplifier with the 4049 (CB4770E)
This different audio amplifier was found in a 90's Electronic Design. The circuit uses components...
Analog-to-Digital Converter – 555 (NI024E)
This circuit converts a resistance in the range between 1 k ohm and 1 MΩ to a signal in a...