HP 25 User Manual

Accessories, Service, and Maintenance 103
charger connected, the batteries will charge with the calculator
OFF or ON . Normal charging times from fully discharged
battery pack to full charge are:
Calculator OFF : 6 hours
Calculator 0 N: 17 hours
Shorter charging periods will reduce the operating time you can
expect from a single battery charge. Whether the calculator is
OFF or ON , the HP-25 battery pack is never in danger of be-
coming overcharged.
Note: It is normal for the battery charger /ac adapter to
be warm to the touch when it is plugged into an ac
outlet.
It is also normal for the HP-25 calculator itself
to be warm to the
touch with the ac adapter /battery
charger connected for battery charging and the HP-25
ON-OFF
switch set to OFF.
Battery Operation
To operate the HP-25 from battery power alone, simply turn the
calculator 0 FF, disconnect the female battery charger plug
from the
rear of the ca lculator , and turn the calculator ON
again. (Even when not connected to the calculator , the battery
charger /ac adapter may be left plugged into the ac outlet.)
Using the HP-25 on battery power gives the calculator full
portability, allowing
you to carry it nearly anywhere. A fully
charged battery pack provides approximately 2 to 5 hours of
continuous operation. By turning the power OFF when the
calculator is not in use, the charge on the HP-25 battery pack
should easily last throughout a normal working day.
Most of the battery power consumed by the calculator is used
to light the display, so you can maximize battery operating time
by displaying
the minimum number of digits necessary while
calculating.
If the H P-25 must be left ON between calculations,
11. 1 is the display that consumes the least power.

HP 25 Specifications

General

Power Source	Rechargeable battery pack
Programming Steps	49
Release Year	1975
Functions	Trigonometric, logarithmic, statistical
Type	Scientific
Dimensions	148 x 80 x 14 mm