HP HP-20S - Getting Started with HP-20 S; Power On and Off

Getting Started
Power On and Off
To turn on your HP-20S, press (the key above the
“ON” label). To turn the calculator off, press either shift
key ([(#) or (¢*]), then (also written (=] or [¢~]
[OFF]).
Since the calculator has Continuous Memory, turning it off does not affect
the information you’ve stored. To conserve energy, the calculator turns itself
off approximately 10 minutes after you stop using it. The calculator’s three
alkaline batteries last approximately a year. If you see the low-battery
symbol (:3) in the display, replace the batteries as soon as possible.
Refer to the appendix for more information.
Adjusting the Display Contrast
To change the display contrast, hold down and press or [-].
Simple Arithmetic Calculations
If you make a typing mistake while entering a number, press (4] to
erase the incorrect digits.
1: Getting Started 9