HP -65 Owner's Handbook Manual page 90

The procedure for using the battery charger is as follows:
1. Make sure the line-voltage select switch on the battery
charger is set to the proper voltage. The two line voltage
ranges are 86 to 127 volts and 172 to 254 volts.
CAUTION
Your HP-65 may be damaged if it is connected to the charger
when the charger is not set for the correct line voltage.
2. Turn the HP-65 power switch to OFF.
3. Insert the battery charger plug into the rear connector of
the HP-65 and insert the power plug into a live power outlet.
4. Slide the power switch to ON. If the W/PRGM-RUN switch
is set to RUN, you should see a display of 0.00.
5. Slide the power switch to OFF if you don't want to use the
calculator while it is charging.
6. At the end of the charging period, you may continue to use
your HP-65 with ac power or proceed to the next step for
battery-only operation.
7. With the power switch turned OFF, disconnect the battery
charger from both the power receptacle and the HP-65.
CAUTION
The use of a charger other than the HP 82002A Battery
Charger supplied with the calculator may result in dam-
age to your calculator.
Battery Operation
Use only the HP 82001A Battery Pack. A fully charged battery
pack provides approximately three hours of continuous opera-
tion. By turning the power off when the calculatoris not in use,
the HP-65's battery pack should easily last throughout a normal
working day.