EC-213 Desktop Talking Calculator (650-0557) Operation Faxback Doc. # 18531 TURNING THE CALCULATOR ON AND OFF Press ON to turn on your calculator. The calculator beeps twice. Press OFF to turn it off. The calculator beeps twice. NOTE: To conserve battery power, the calculator automatically turns off if you do not press any key for about 7 minutes. ADJUSTING THE VOICE ANNOUNCEMENTS' VOLUME The VOLUME control lets you turn the calculator's voice announcements off or on and adjust the sound level. For louder sound, set VOLUME to the right position. For normal sound, set VOLUME to the middle position. To turn off the sound, set VOLUME to the left position. HEARING CALCULATION RESULTS IN UNITS OR DIGITS. To choose between hearing calculation results in digits or units, press UNITS/DIGITS. When you press UNITS/DIGITS and it beeps once, the EC-213 will announce results in units (for example, it announces 123 as "one hundred twenty-three"). When you press UNITS/DIGITS and it beeps twice, the EC-213 will announce results in digits (for example, it announces 123 as "one two three"). HEARING THE ANSWER ONLY You can choose between hearing every key entry and hearing only calculation results by pressing ANSWER ONLY. When you press ANSWER ONLY and the EC-213 beeps once, it announces only the results of calculations after you press =, %, MR, or REP. When you press ANSWER ONLY and the EC-213 beeps twice, it announces every key entry (including numbers and functions) and the results of any calculations. REPEATING A VOICE ANNOUNCEMENT Press REP to repeat a voice announcement of the last entry or the last calculation result. CORRECTING ENTRY ERRORS If you enter an incorrect number, press CE once. Then enter the correct number and proceed with your calculation. If you enter an incorrect function key other than a memory key, % or =, simply press the correct key and continue. For example, if you press 7 x divide + 5 =, the calculator performs 7 + 5 = and 12 appears on the display. DISPLAY ERRORS ERROR (overflow error) appears when you: Attempt a calculation where the result exceeds 8 digits to the left of the decimal point. Try to add a value to the contents in memory and the result exceeds 8 digits (the contents in memory are not changed). Attempt to divide a number by 0. To remove the error but keep the display, press CE once. To clear the display, press CE twice or AC once. Approximating Overflow Errors If you perform a calculation that results in an overflow error, you can approximate the correct answer (to 8 significant digits) by following these steps. 1. Count the number of digits displayed to the left of the decimal point. 2. Remove the decimal point. 3. Add as many zeros to the right of the result as there were digits to the left of the decimal point. For example: If the display shows ERROR and 1. 0142064, the approximate answer is 101,420,640. If the display shows ERROR and 319.70347, the approximate answer is 31,970,347,000. CALCULATIONS EXAMPLES Basic Arithmetic Calculations You Press You See 256 + 378 = 634. 471 - 223 = 248. 15.5 x 2.3 = 35.65 17.2 divide 2.5 = 6.88 Mixed Calculations You Press You See 24 + 36 - 75 MINUS - x 8 divide 9 = 13.333333 Percentage, Add-On, and Discount Calculations You Press You See 720 x 20% 144. 540 + 30% 702. 800 - 20% 640. Constant Function Calculations For multiplication, the first value you enter is the constant. For addition, subtraction, and division, the second value is the constant. You Press You See 5 x 7 = 35. 9 = 45. 10 = 50. 100 + 5 = 20. 200 = 40. 300 = 60. Power Calculations Example: 7 to the sixth power = 117.649 You Press You See 7 x = = = = = 117649. Memory Calculations To clear the current value from memory (set it to 0), press MC (memory clear) once. To add the displayed value to the current value in memory, press M+. MEMORY appears on the display when a value is stored in the calculator's memory. To subtract the displayed value from the current value in memory, press M-. To recall the value from memory, press MR (memory recall) once. You Press You See MC 0. 4 x 5 M + MEMORY 20. 7 - 2 M- MEMORY 5. MR MEMORY 15. (JC 11/7/95)