HP 33s - Manual (Page 296)

A–2 Support, Batteries, and Service
A: You must clear a portion of memory before proceeding. (See appendix B.)
Q: Why does calculating the sine (or tangent) of π radians display a very small
number instead of 0?
A: π cannot be represented exactly with the 12–digit precision of the calculator.
Q: Why do I get incorrect answers when I use the trigonometric functions?
A: You must make sure the calculator is using the correct angular mode ( Ÿ
{}, { }, or { } ).
Q: What does an annunciator in the display mean?
A: It indicates something about the status of the calculator. See "Annunciators" in
chapter 1.
Q: Numbers show up as fractions. How do I get decimal numbers?
A: Press { ‹ .
Environmental Limits
To maintain product reliability, observe the following temperature and humidity
limits:
„ Operating temperature: 0 to 45 °C (32 to 113 °F).
„ Storage temperature: –20 to 65 ° C (–4 to 149 °F).
„ Operating and storage humidity: 90% relative humidity at 40
°
C (104
°
F)
maximum.
Changing the Batteries
The calculator is powered by two 3-volt lithium coin batteries, CR2032.
Replace the batteries as soon as possible when the low battery annunciator ( ¥ )
appears. If the battery annunciator is on, and the display dims, you may lose data.
If data is lost, the  &  message is displayed.