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Altera_Forum's avatar
Altera_Forum
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18 years ago

Need creative ideas for "inspiration" on fun project

I want to build a simple toy/fun project with an FPGA, but I need to seriously McGuyver a certain part. I am going to need a small, electrically operated device I can attach to FPGA that makes lots of LOUD NOISE. It needs to be small, maybe the size of a cigarette lighter. I dont care if it whistle, beeps, buzzess booms or whatever, i'd guess a few seconds worth of noise maybe like you'd get from a smoke alarm. And I absolutely assure you I am not trying to make one of those.

4 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    18 years ago

    Maybe one of those loud little speakers on old modems would work? Or possibly just use the audio output jack and hook up an amplified speaker.

  • Altera_Forum's avatar
    Altera_Forum
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    18 years ago

    You didn’t state which FPGA, but assuming you grab an older classic one that can support 5V outputs, you can then grab a piezo buzzer from an old smoke alarm and have the FPGA drive it directly with steady state voltage. Or you can grab a musical buzzer from one of those fancy hallmark cards and drive it with the FPGA too :D

    Another option is grab a small speaker and build an oscillator inside the chip to the frequency of your choice. Then select the I/O standard and appropriate power supply that will produce a volume level of what you desire.

    BTW, it's illegal to remove existing smoke alarms from a building.
  • Altera_Forum's avatar
    Altera_Forum
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    18 years ago

    Get any '5 year old kids' toy space ray gun, bust it open to get just the sound box and battery parts. Then just use the FPGA to be the 'trigger' to ground. Might need a transistor in the loop to limit the current.

  • Altera_Forum's avatar
    Altera_Forum
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    18 years ago

    :eek: The user could act as a loudspeaker, given a trigger of sufficient power.