4 ms·

It doesn't have to be always on, it could be remotely controlled.

• danellis 11y ago
  It's not powered up, though. That's why it lasts so long on one battery. The button wakes it up.
  • userbinator 11y ago
    There's a 32kHz RTC oscillator in the MCU, which can be programmed to periodically wake it up as well. Without analysing the firmware you wouldn't be able to confirm for sure what it's doing. I suppose one exercise for those inclined would be to reprogram it to listen (perhaps only during the daytime) and see how long it lasts. You wouldn't need high fidelity so a low sample rate would be enough.
    • danellis 11y ago
      > Without analysing the firmware you wouldn't be able to confirm for sure what it's doing. It's on your own network, so it's trivial to know when it's communicating and with whom. In principle, it could periodically wake and poll a C&C server to see whether it should start streaming audio or not.
      • ceequof 11y ago
        Nothing forces it to be on your network. If there's a neighbor with open wifi, or easily cracked wifi, or wifi Amazon already has the key for, (from an Amazon tablet/phone that's been connected to it before) then it could talk on that instead.
        • ars 11y ago
          You could measure power draw on the battery and make sure no power is ever drawn except when the button is pressed.
• deleted 11y ago
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