Free Circuit Diagram

Feedback in public address amplifier is something that should be avoided. The ideal solution is by adjusting the microphone and the speaker position, but it’s not always possible in many situation. Using frequency shifter to change the output frequency 10Hz lower than the input frequency can solve the problem, but it’s too expensive for [...]

This circuit is not a voice operated switch (VOX) because this circuit is too dumb to differentiate between musical sound or human voice. This is rather a sound activated than voice activated. One interesting application is to control your disco lighting automatically by the musical sound from high power amplifier, when the music signal is [...]