Yes, that surprised me too. But do you have any idea how your phone's alarm can ... | Hacker News

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		gpvos on Nov 4, 2019 \| parent \| context \| favorite \| on: I tried to adjust the time on my alarm clock Yes, that surprised me too. But do you have any idea how your phone's alarm can ring when the battery is dead? Does it have a second battery?

smichel17 on Nov 4, 2019 [–]

Most phones turn off before the battery is truly 100% dead.

cesarb on Nov 5, 2019 | [–]

IIRC, some of these old phones do have a second "coin cell" battery, which keeps the clock running even when the main battery is removed (the SIM card is usually below the battery, so you have to remove it to exchange the SIM card).

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