1. Introduction
The LUCKY Portable Fish Finder (Model: RM) is a versatile and user-friendly device designed to enhance your fishing experience. Featuring an updated 2.4-inch TFT color LCD screen, it provides clear and professional display of underwater contours, water depth, water temperature, and fish information (size and depth). This portable fish finder offers two primary user modes: TRANSDUCER and SIMULATION, allowing you to familiarize yourself with its functions before heading out to fish. With a wired operating distance of 26 feet and a depth detection capability of up to 328 feet, it utilizes a 45° beam angle with 200Khz sonar for accurate readings. The device is rechargeable via USB and offers approximately 5 hours of continuous operation on a full charge, with adjustable screen brightness for optimal visibility in various lighting conditions.

Figure 1.1: The LUCKY Portable Fish Finder main unit and its wired transducer.
2. Safety Information
Please read and understand the following safety guidelines before operating the LUCKY Portable Fish Finder:
- The optimal working temperature for this device is between -10°C and 50°C (14°F to 122°F). Operating outside this range may affect performance or damage the unit.
- Ensure all connections are secure before use, especially the transducer cable, to prevent water ingress.
- Do not attempt to disassemble or modify the device, as this will void the warranty and may cause damage or injury.
- Keep the device and its components away from extreme heat sources, open flames, and corrosive materials.
- When using the transducer from a moving boat, ensure the speed is lower than 5 mph for accurate readings and to prevent damage to the transducer.
- Always handle the transducer with care to avoid damaging the sensor surface.
3. Package Contents
Verify that all items are present in your package:
- LUCKY Portable Fish Finder Main Unit
- Wired Sonar Transducer with Float
- USB Charging Cable
- USB AC Adapter
- Micro Auto Charger
- Mounting Bracket
- Neck Strap
- Instruction Manual (this document)

Figure 3.1: All components included in the LUCKY Portable Fish Finder package.
4. Product Overview
The LUCKY Portable Fish Finder consists of a main display unit and a wired sonar transducer. Understanding the different parts and their functions is crucial for effective operation.
4.1. Main Unit Features

Figure 4.1: Detailed view of the main unit with labeled components.
- Display Screen: 2.4-inch TFT color LCD for displaying sonar data, depth, temperature, and settings.
- Power On/Off Button: Located at the bottom left, used to power the device on or off.
- Menu Key: Accesses the main menu for settings adjustments.
- Arrow Buttons (Left/Right/Up/Down): Used for navigation within menus and adjusting settings.
- Battery Indicator: Displays the current battery level.
- Wired Signal Indicator: Shows connection status with the transducer.
- Water Depth & Temperature Display: Real-time readings of water conditions.
- Fish Icon with Depth: Graphical representation of fish and their approximate depth.
- Bottom Contour: Visualizes the underwater terrain.
- Zoom Range: Indicates the current depth range being displayed.
4.2. Sonar Transducer
The wired sonar transducer is the component that emits sonar waves into the water and receives the echoes to detect underwater objects and terrain. It is connected to the main unit via a long cable and includes a float for surface deployment.

Figure 4.2: The wired sonar transducer, capable of 328 feet depth detection with a 45° beam angle.
5. Setup
Follow these steps to set up your LUCKY Portable Fish Finder for first use:
- Charge the Main Unit: Before initial use, fully charge the fish finder's main unit using the provided USB charging cable and AC adapter or micro auto charger. The battery indicator on the screen will show charging progress.
- Connect the Transducer: Locate the port at the top of the main unit. Carefully insert the plug from the wired sonar transducer into this port. Ensure a firm and secure connection.
- Power On: Press and hold the Power On/Off button (bottom left) for a few seconds until the LUCKY logo appears on the screen.
- Select Mode: Upon powering on, you will be prompted to select a mode:
- TRANSDUCER Mode: For actual fish detection in water.
- SIMULATION Mode: Allows you to explore all functions and display features without being in water. This is recommended for familiarization.
- Deploy the Transducer:
- From Shore/Dock: Cast the sonar transducer as far as you can into the water. The float will keep it suspended at the surface.
- From Boat/Kayak: Attach the transducer to the boat hull using the mounting tabs and bracket, ensuring the transducer is approximately 1 inch underwater. For optimal readings, keep the boat speed below 5 mph.
6. Operating Instructions
The LUCKY Portable Fish Finder offers various settings and display options to customize your fishing experience.
6.1. Understanding the Display
The 2.4-inch TFT color LCD screen provides comprehensive information:
- Underwater Contour: Displays the shape of the seabed or lakebed. The device offers 3 color display modes (blue, red, gray) for clearer and more professional visualization.
- Water Depth: Numerical reading of the current water depth.
- Water Temperature: Numerical reading of the water temperature.
- Fish Size & Depth: Fish are represented by icons (large, middle, small) with their corresponding depth.

Figure 6.1: Examples of updated display modes for underwater contour.

Figure 6.2: Fish alarm feature indicating different fish sizes.
6.2. Adjusting Settings
Access the main menu by pressing the Menu key to customize the following settings:
- Sensitivity: Controls the level of detail shown on the display. Adjust from 1 to 10. Lower sensitivity is recommended for clear water.
- Screen Brightness: Adjust for optimal visibility in different lighting conditions (day or night).
- Depth Range: Set the maximum depth displayed.
- Zoom: Magnify a specific depth range for more detailed observation.
- Depth Alarm: Set an alarm to sound when the water depth falls below a specified value.
- Fish Alarm: Activates an audible alert when fish or schools of fish are detected. Can distinguish between large, middle, and small fish.
- Units: Change measurement units for depth (FT/M) and temperature (°C/°F).
- Language: Select your preferred language for the interface.
6.3. Fishing Applications
The LUCKY Portable Fish Finder is suitable for various fishing environments:
- Ice Fishing
- River Fishing
- Sea Fishing
- Shore Fishing
- Kayak Fishing
- Boat Fishing

Figure 6.3: Versatile applications of the fish finder in various fishing environments.
7. Maintenance
Proper maintenance ensures the longevity and optimal performance of your fish finder:
- Cleaning: After each use, especially in saltwater, rinse the transducer and main unit with fresh water. Wipe them dry with a soft cloth. Do not use abrasive cleaners or solvents.
- Storage: Store the device in a cool, dry place away from direct sunlight and extreme temperatures. Ensure the unit is fully charged before long-term storage to preserve battery life.
- Battery Care: Recharge the unit regularly, even if not in use, to maintain battery health. Avoid completely draining the battery frequently.
- Transducer Cable: Inspect the transducer cable regularly for any signs of wear, cuts, or damage. Replace if necessary to maintain signal integrity and prevent water damage.
8. Troubleshooting
If you encounter issues with your LUCKY Portable Fish Finder, refer to the following common problems and solutions:
| Problem | Possible Cause | Solution |
|---|---|---|
| No display/Unit won't turn on | Low battery; Loose transducer connection; Power button not held long enough. | Charge the unit fully. Ensure transducer cable is securely plugged in. Press and hold the power button for 3-5 seconds. |
| Inaccurate depth readings | Transducer not fully submerged; Air bubbles under transducer; Boat speed too high; Water too shallow/deep. | Ensure transducer is 1 inch underwater. Reposition transducer to avoid bubbles. Reduce boat speed (below 5 mph). Check device's depth range limits (328ft max). |
| No fish icons displayed | Low sensitivity setting; No fish present; Transducer not positioned correctly. | Increase sensitivity setting. Move to a different fishing spot. Ensure transducer has a clear path to the water. |
| Screen difficult to read in sunlight | Low screen brightness setting. | Adjust screen brightness in the settings menu. |
9. Specifications
| Feature | Detail |
|---|---|
| Brand | LUCKY |
| Model Name | RM |
| Part Number | HJY1108-CT |
| Power Source | Battery Powered |
| Screen Size | 2.9 Inches (Note: Description states 2.4 inches, using specification data) |
| Display Type | LCD |
| Item Weight | 400 Grams |
| Product Dimensions (LxWxH) | 5.31" x 2.76" x 1.1" |
| Maximum Measuring Depth | 100 Meters (328 Feet) |
| Beam Angle | 45° with 200Khz |
| Operating Distance (Wired) | 26 Feet |
| Battery Life (Continuous) | Approx. 5 hours |
| Working Temperature | -10°C to 50°C (14°F to 122°F) |
| Mounting Type | Surface Mount |
10. Warranty & Support
The LUCKY Portable Fish Finder comes with a 1-Year Warranty from the manufacturer.
For technical support, troubleshooting assistance, or warranty claims, please contact LUCKY customer service through the retailer where you purchased the product or visit the official LUCKY Store on Amazon:
Visit the LUCKY Store on Amazon
Please have your product model (RM) and part number (HJY1108-CT) ready when contacting support.




