This circuit produces the sound of percussion such as blocks, drum, bell, etc. The frequency depends on the marked capacitors, which can have a wide range of values depending on the desired sound.
This circuit is a driver for R-2R network of AD converters. We found it in manufacturer...
This circuit was found in an American publication from the 60's. The transistor is made of...
This circuit produces an audio tone on the speaker or magnetic capsule. Rx must be such that added...