Hi,
Last night, kept hearing a short little "tune" (1-2 seconds) throughout the night. Eventually convinced myself it was
*not* part of a bizarre dream sequence. Come morning, I actively sought it out.This proved difficult as it would only occur every 4 or 5 minutes and was just a second or two in duration (so hard to localize).
Turned out to be a cell phone complaining of low battery (?) [I don't use a cell phone, so would never have considered this possibility].
Phone was "off" so obviously something is waking itself from deep sleep, periodically, to test the battery and then complain that it is low. (presumably, there is some value to this feature?)
Of course, we all know smoke/CO detectors like to chirp interminably as their batteries fail. Lacking any real smarts, it is understandable why a smoke detector will chirp *every* "minute" since it basically sits dormant most of the time and just wakes up to "sniff the air" (and the battery!) before going back to sleep.
But, what's the rationale in having a *smart* device (e.g., cell phone) take the same sort of uninspired approach? I.e., assuming there is some value in warning the user WHILE THE PHONE IS OFF that the battery needs a charge, why such a naive implementation? Wouldn;t it make more sense to backoff (exponentially?) with the notifications?
I assume if the user *used* the phone in this time, he would be more directly notified of the "low battery" status. So, why waste battery playing silly little songs every 5 minutes indefinitely?
And, how does this rationale apply to other "persistent" indicators? E.g., the "fasten seat belt", "door open", "headlights are still on", "you forgot your keys, dummy", etc.