Modulator lights depending upon noise (in the room)
Has been intended for deaf character as acoustic converter. Character of device is compression of dynamics of sound. In this way achieved proportionality between clamor and light powers. Potentiometer or trimer adjusts the amplification of sound dynamics.
Warning: complex is not separated from net voltage. Therefore the housing of microphone and potentiometer has been needed is isolated, and box for device has been needed plastic and good block probable touch user with the complex.
Price of finished complex (without box): 370 HRK (50 euro)