Show HN: Capacitor Alarm Clock

(github.com)

45 points | by arcaege 3 days ago

12 comments

  • ahoka 0 minutes ago
    Is this not technically an IED?
  • rpaddock 26 minutes ago
    This reminded me of a Blog entry I wrote about in 2013 on "Massive Electro-Pyrotechnic Initiator Chip Resistor (MEPIC)". These are 0805 chip resisters that are by design meant to let out the Magic Smoke that runs all electronic parts.

    Sadly I could not get free samples from my Vishay Rep, that I was in good standing with. MEPIC85N8R0KTT come in lots of 10,000 to buy.

    Be sure to check out the application note "A Guide to Using EPIC / MEPIC Igniters in Pyrotechnic Applications".

    https://www.vishay.com/en/product/53058/

    National Semiconductor, bought by TI, used to make a similar part, check out the application note:

    https://www.ti.com/lit/an/snoa217/snoa217.pdf

    This is what I wrote about the MEPIC parts a long time ago:

    "MEPIC resistors, also known as bridge resistors, are resistive elements that convert electrical energy into heat energy in a precise electro-thermal profile for the purpose of initiating a series of pyrotechnic events in a controlled energetic reaction. [They go BOOM on command, which is different than Rapid Spontaneous Self-Disassembly.]

    The new Vishay Sfernice resistor is optimized for electronic igniter applications in automotive safety systems for the deployment of airbags and other safety devices; digital blasting in mining applications; and in fireworks applications for better synchronization of fireworks, music, and special effects.

    With firing energy down to 1.5 mJ and a typical ohmic range of 2 Ohms (+/- 10 %), the device provides designers with very predictable, reproducible, and reliable behavior.

    Offered in the standard 0805 case size for the wraparound and flip chip versions, with other sizes available upon request, the resistor features easy set-up of firing levels, and is compatible with various pyrotechnic compositions.

    Offering ESD withstanding to 25 kV without extra protection, the MEPIC resistor's performance meets no fire/all fire conditions and the requirements of USCAR, AKLV16, and major car manufacturer standards.

    The device is RoHS-compliant and conforms to Vishay "Green" standards. [Is it not great that Fuzes are 'Green'?]"

  • peterabbitcook 32 minutes ago
    So it’s not UL listed?

    Do you need the 15V input to torch the capacitors and run the relays? Could I use a 5V USB ESP32 dev board instead, and just put a boost circuit or MOSFET on the relay load side for the explosion circuit when it needs to go off, or are there other components that need the higher voltage?

  • sscaryterry 23 minutes ago
    Try this with a tantalum capacitor. Careful not to lose an eye...
  • andai 1 hour ago
    There's a video demonstration about halfway down the GitHub

    https://github.com/ArcaEge/capacitor-alarm-clock#Demo

  • beeforpork 1 hour ago
    That sounds completely safe and healthy! Hmmmm, I love the smell of vaporized electrolyte, particularly when waking up!
    • fc417fc802 46 minutes ago
      I feel like a wire detonator would be safer plus the consumables would be cheaper however even then I doubt vaporized copper or aluminum is good for you. Honestly just roll some firecrackers and use the ESP to light them off.
  • felooboolooomba 28 minutes ago
    Sorry I'm late, the capacitor didn't blow.

    Did anyone else smell capacitors when they watched the video? The brain does funny things.

  • uberex 1 hour ago
    Based. Unhinged. Don't try this at home.

    But it is also art. It represents the waste in our devices that play out over 1-4 years (or say a few weeks for a vape) but in one night.

    But yeah. Don't do it. Indoors? wtf!!!!

    • nmeofthestate 3 minutes ago
      Oh no. I quite liked this until you said it was art that Represented something.
  • bilsbie 47 minutes ago
    What’s happening at the electron level that makes them do this? Anyone know?
  • adnaahmed 46 minutes ago
    the alarm clock for the ai age, it needs an LLM
    • KaiserPro 8 minutes ago
      It is an LLM

      a Life limiting machine

  • block_dagger 48 minutes ago
    How about a flux capacitor clock?
  • kavyanshkh 1 day ago
    gng thats crazy!