This circuit is from Motorola's Linear Interface ICs of 1993. The circuit can be powered by symmetrical 6 to 12 V voltages and for a stereo version, two channels must be built.
Placed in the vicinity of a telegraphic transmitter (CW), this circuit produces an audible signal on...
Damped oscillators can be used to produce sound from percussion instruments such as the triangle, bell,...
We found this circuit in a 1983 English magazine, but it can be easily assembled with the BC548...