Pentax PocketJet 3 - Manual (Page 51)

Charging the Battery
Note: Batteries are shipped from the factory uncharged. Pentax
recommends that a complete charging cycle (following steps 1
through 3 below) be completed before using the battery for the
first time.
1. Make sure the printer is connected to an AC power outlet with the
AC adapter and power cord or a DC power cord.
2. Make sure the printer is off.
3. Press the main switch and hold it down for a few seconds until the
POWER indicator light begins to blink. This puts the printer in
Charge Mode and starts the charging of the battery.
The POWER indicator light blinks until charging is complete.
The maximum time to charge to 100% capacity is approximately 120
minutes. A new battery at 100% charge will yield approximately
100 pages of printing.
When the printer finishes charging the battery, it automatically turns
itself off, and the POWER indicator light goes off.
Note that when the printer is connected to an external source of power,
it will constantly draw approximately 20 mA to trickle charge the
battery.
Stopping the Charge Process
If you want to stop the printer while it is in Charge mode, press the
main switch twice quickly.
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