1. Introduction
This manual provides detailed instructions for the operation and maintenance of your CATIGA CS-183 Scientific Calculator. Designed for students and professionals, the CS-183 offers a wide range of functions for mathematics, science, engineering, and business applications. Please read this manual thoroughly to ensure proper use and to maximize the calculator's capabilities.

Figure 1.1: Front view of the CATIGA CS-183 Scientific Calculator, displaying its two-line screen and comprehensive keypad.
2. Getting Started
2.1. Package Contents
- CATIGA CS-183 Scientific Calculator
- Protective Sliding Cover
- 2 CR2 Batteries (pre-installed or included separately)
- User Manual (this document)
2.2. Battery Installation
The CATIGA CS-183 requires two CR2 batteries for operation. If the display is dim or blank, replace the batteries following these steps:
- Ensure the calculator is powered off.
- Locate the battery compartment on the back of the calculator.
- Using a small screwdriver, carefully remove the screw securing the battery cover.
- Remove the battery cover.
- Insert two new CR2 batteries, ensuring correct polarity (+/-) as indicated inside the compartment.
- Replace the battery cover and secure it with the screw.
2.3. Power On/Off
- To power on the calculator, press the [ON] button.
- To power off the calculator, press [SHIFT] then [AC] (OFF).
3. Keypad Layout and Display
The CS-183 features an ergonomic keyboard with responsive buttons. Keys are grouped by function for intuitive use.

Figure 3.1: Close-up view of the CATIGA CS-183's ergonomic keyboard, highlighting key responsiveness.
3.1. Two-Line LCD Screen
The calculator is equipped with a two-line LCD screen. The upper line displays the input expression or formula, while the lower line shows the calculation result. This allows for easy verification of your input and comparison with the output.

Figure 3.2: The two-line display showing an input calculation on the top line and its result on the bottom line.
4. Operating Instructions
The CATIGA CS-183 supports over 200 functions, categorized for ease of use.

Figure 4.1: An overview of the basic, scientific, statistical, and memory functions supported by the CS-183 calculator.
4.1. Basic Calculations
- Arithmetic Operations: Use [+], [-], [x], [/] for addition, subtraction, multiplication, and division. Press [=] to get the result.
- Percentages: Input the number, then [x], the percentage value, and [%].
- Fractions: Use the [d/c] or [a b/c] key to input and convert fractions.
- Parentheses: Use [(] and [)] to define calculation order. The calculator supports up to 24 levels of parentheses.
4.2. Scientific Functions
Access scientific functions by pressing the function key directly or by pressing [SHIFT] followed by the desired function key (indicated above the key).
- Trigonometry: [sin], [cos], [tan] and their inverse functions ([SHIFT] + [sin-1], etc.).
- Hyperbolic Functions: [hyp] followed by [sin], [cos], [tan].
- Logarithms: [log] (base 10) and [ln] (natural logarithm).
- Powers and Roots: [x2], [x3], [√], [3√], [xy].
- Factorials, Permutations, Combinations: Use [x!], [nPr], [nCr].
- Angle Unit Conversions: Switch between Degrees (Deg), Radians (Rad), and Grads (Gra) using [MODE].
- Coordinate Conversion: Convert between Polar and Rectangular coordinates using [Pol(x,y)] and [Rec(r,θ)].
- Engineering Notation: Use [ENG] to display results in engineering notation.
4.3. Statistical Calculations
The calculator supports various statistical calculations. Enter STAT mode using [MODE] and select the desired statistical type (e.g., SD for Standard Deviation, REG for Regression).
- Standard Deviation: Input data points and use the appropriate keys to calculate mean, standard deviation, etc.
- Regression: Input paired data (x, y) to perform linear regression and calculate coefficients.
4.4. Memory and Replay Functions
- Memory Storage (STO): Store a value into a memory variable (A-F, X, Y, M) using [STO] followed by the variable key.
- Memory Recall (RCL): Recall a stored value using [RCL] followed by the variable key.
- Memory Plus (M+): Adds the displayed value to the independent memory.
- Memory Minus (M-): Subtracts the displayed value from the independent memory.
- Replay Function: Use the directional arrow keys [▲], [▼], [◄], [►] to scroll through previous calculations and edit expressions.
5. Maintenance and Care
Proper care will extend the life of your calculator.
- Cleaning: Wipe the calculator with a soft, dry cloth. Do not use abrasive cleaners or solvents.
- Storage: Store the calculator in a cool, dry place. Use the included protective sliding cover to prevent damage to the keys and screen.
- Battery Replacement: Replace batteries promptly when the display becomes dim to avoid data loss or malfunction.

Figure 5.1: The CATIGA CS-183 calculator shown with its protective sliding cover, designed for durability and longevity.
6. Troubleshooting
If you encounter issues with your calculator, refer to the following common problems and solutions:
| Problem | Possible Cause | Solution |
|---|---|---|
| Display is blank or dim. | Low or dead batteries. | Replace the two CR2 batteries. |
| Calculator does not turn on. | Batteries incorrectly installed or dead. | Check battery polarity or replace batteries. |
| Incorrect calculation results. | Incorrect mode setting (e.g., angle units), syntax error, or internal malfunction. | Check angle mode (Deg, Rad, Gra). Review input syntax. Perform a reset. |
| Keys are unresponsive. | Dust/debris under keys or internal issue. | Gently clean around keys. If problem persists, perform a reset. |
| Calculator freezes. | Temporary software glitch. | Press the [RESET] button located on the back of the calculator using a thin, pointed object (e.g., a paperclip). This will clear all memory and settings. |
7. Specifications
Detailed technical specifications for the CATIGA CS-183 Scientific Calculator.

Figure 7.1: The CATIGA CS-183 calculator displaying its approximate dimensions of 7.12 inches in length and 4.5 inches in width.
| Feature | Detail |
|---|---|
| Model Number | 8541735422 |
| Product Dimensions | 6.3 x 3.25 x 0.1 inches |
| Item Weight | 4.8 ounces |
| Power Source | Battery Powered (2 CR2 batteries included) |
| Screen Type | 2-Line LCD Display |
| Screen Size | 3 Inches (visible diagonal) |
| Calculator Type | Scientific, Business, Engineering |
| Functions | Over 200 functions including percentages, trigonometry, fractions, statistics, regressions, permutations/combinatorics, memory, and replay. |
8. Warranty and Support
CATIGA is committed to providing reliable products and customer satisfaction.
8.1. Return Policy
This product is eligible for a 30-day unconditional return guarantee from the date of purchase. Please refer to your retailer's return policy for specific instructions on processing returns or replacements.

Figure 8.1: Visual representation of the 30-day unconditional return guarantee.
8.2. Customer Support
For any questions, technical assistance, or support needs, please contact CATIGA customer service. Support is available via phone from 9 AM to 5 PM PST, and 24/7 online support may also be available.

Figure 8.2: Icon indicating 24/7 customer support availability.

Figure 8.3: Icon indicating lifetime support available by phone during specified hours.


