One-IC two-tones Siren


Posted on Feb 6, 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

    milliohmmeter with AT90S2313
    High-efficiency-flyback-voltage-converter
    Crystal oscillator simulation
    Bots Circuit Designs
    AVR Interrupts and binary counter
    xilinx Documenting Digital Design Schematics and Figures
    dvd burner laser pointer proper way 18
    The General Electric XT-1-A AM transmitter
    A Regenerative Receiver with AGC for 80 and 40 Meters
    An SCR Based Burglar Alarm



    Top