One-IC two-tones Siren


Posted on Feb 7, 2014

This circuit is intended for children fun, and is suitable to be installed on bicycles, battery powered cars and motorcycles, but also in models and other games. With SW1 positioned as shown in the circuit diagram it reproduces the typical dual tone sound of Police or Fire-brigade cars, by the oscillation of IC1A and IC1B gates. With SW1 in the ot


One-IC two-tones Siren
Click here to download the full size of the above Circuit.

her position, the old siren sound increasing in frequency and then slowly decreasing is reproduced, by pushing on P1 that starts oscillation in IC1C and IC1D. The loudspeaker, driven by Q1, should be of reasonable dimensions and well encased, in order to obtain a more realistic and louder output. Tone and period of the sound oscillations can be varied changing the values of C1, C2, C5, C6 and/or associated resistors. There is no power switch: leave SW1 in the low position (old-type siren) and the circuit consumption will be negligible.




Leave Comment

characters left:

Related Circuits

  • New Circuits

    .

     


    Popular Circuits

    Audio noise generator
    Logic test probe with memory
    Balanced-modulator
    bicycle back safety light
    Energy Saving Lighting with One-Shot Timer Circuit
    Moduler Preamplifier Circuit
    NMEA 2000 CAN Marine Interface
    ATmega8 and Hall Sensor A1302
    Stylophone schematic Electronic marvel from years ago
    ACU7505 chip MP3 player memory circuit
    AM radio circuit chip



    Top