I recently discovered that the LCD clock on my P250 is powered by a battery other than the main -- the main battery has been disconnected for weeks, and the clock is still on, and keeping time.
As I have to assume the battery is in the headset somewhere, and probably difficult to replace, I figure I'll get a bunch of dollar-store stick on clocks at some point, and just slap that sucker on over the clock, when the time comes.
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