FIRE SIREN USES FLASHER


Posted on Feb 6, 2014

Low-drain circuit operating from 1. 5-V cell uses National LM3909 flasher IC to simulate fire-alarm siren. Pressing button produces rapidly rising wail, with tone coasting down in frequency after button is released. Sound from loudspeaker resembles that of motor-driven siren. Volume is adequate for child`s pedal car. -P. Lefferts, Power-Miser Flashe


FIRE SIREN USES FLASHER
Click here to download the full size of the above Circuit.

r IC Has Many Novel Applications, EDN Magazine, March 20, 1976, p 59-66.




Leave Comment

characters left:

Related Circuits

  • New Circuits

    .

     


    Popular Circuits

    clap sensor construction
    a single transistor smart battery charger
    static 0 to 9 display
    Linkswitch-lp Design Guide Flyback Design Guide
    UHF Indicator - Wavemeter
    One-IC two-tones Siren
    EXPANDED SCALE DC VOLTMETER
    LM386 making music with a voice-activated lights circuit
    Stimulated simple motor speed control circuit
    Digital circuit touch delay circuit 5



    Top