1. Introduction
The Walfront AT 100M Pro is a versatile automatic antenna tuner and power standing wavemeter designed for amateur radio enthusiasts. It supports a wide frequency range from 1.8 MHz to 30 MHz and is compatible with various radio stations and antenna types. Featuring both manual and automatic tuning modes, an OLED display, and a built-in 3300mAh lithium battery, this compact and portable device is ideal for both fixed and portable operations.
2. Safety Information
- Ensure proper grounding of the device and antenna system to prevent electrical hazards.
- Do not exceed the specified power limits for the device at different frequencies and modes to avoid damage. Refer to the specifications section for details.
- Keep the device away from water, moisture, and extreme temperatures.
- Use only the provided USB Type-C cable for charging.
- Do not attempt to disassemble or modify the device, as this will void the warranty and may cause damage or injury.
3. Package Contents
Verify that all items are present in the package:
- 1 x Antenna Tuner Power Standing Wavemeter (AT 100M Pro)
- 1 x L Wrench
- 1 x USB Cable (Type-C)
- 1 x Foot Pad Set
- 1 x User Manual

4. Product Overview
4.1 Physical Features
The AT 100M Pro features a compact and portable design with an aluminum alloy shell, ensuring durability. Its dimensions are approximately 154mm x 74mm x 29mm, making it easy to carry for outdoor and portable operations.

4.2 Interface and Display
The device is equipped with an OLED display that provides clear information on various operating parameters. It supports six status interfaces for comprehensive monitoring:
- User Storage Interface: For saving and recalling settings.
- Bar Power Standing Meter Interface: Real-time display of current power and standing wave meter, supporting up to 150W.
- Large Font Interface: Provides a clearer view of standing wave and power meter values.
- Standing Curve Interface: Displays the changing trend of the standing wave in real-time during transmission.
- Power Chart Interface: Shows the output power change trend in real-time during transmission.
- Relay and Battery Voltage Status Interface: Displays the current relay status of capacitance and inductance, and allows manual adjustment.

4.3 Connectivity
The device features standard RF connectors for antenna and radio input, a ground terminal, a 3.5mm jack for a CW key, and a USB Type-C port for charging.

5. Setup
5.1 Initial Charging
Before first use, fully charge the built-in 3300mAh lithium battery using the provided USB Type-C cable and a 5V 1A power source. The charging LED will be red during charging and turn green when fully charged. A full charge takes approximately 4 hours.
5.2 Connecting to Radio and Antenna
- Connect your radio's antenna output to the IN connector on the AT 100M Pro.
- Connect your antenna to the ANT connector on the AT 100M Pro.
- Ensure a proper ground connection by connecting the GND terminal to your station's ground system.
- No professional data cable is needed for operation.

6. Operating Instructions
6.1 Power On/Off
Use the OFF/ON switch located on the front panel to power the device on or off.
6.2 Tuning Modes
The AT 100M Pro supports two tuning modes: Manual Tuning and Auto Tuning.
- Auto Tuning: Press the AUTO button to initiate automatic tuning. The device will automatically adjust the capacitance and inductance to achieve the lowest SWR.
- Manual Tuning: Use the TUNE button to enter manual tuning mode. You can then adjust the capacitance and inductance values as needed to optimize SWR.
6.3 Understanding the Display Interfaces
The OLED display offers various views to monitor your antenna system's performance:
- PWR&SWR Meter: Shows real-time forward power (FWD), reflected power (REF), and Standing Wave Ratio (SWR).
- Large Font Interface: Provides an enlarged display of key SWR and power values for easy reading.
- SWR Chart: Visualizes the SWR trend over time during transmission.
- PWR Chart: Visualizes the output power trend over time during transmission.
- Relay State: Displays the current state of internal relays, indicating capacitance and inductance values. These can be adjusted manually.
- Configuration Menu: Long-press the 'Tune' button to access the menu and customize up to 14 functional parameters, such as BEEP ON/OFF, TUNE AUTO/MANUAL, TUNE COUNT, and AUTO SWR threshold.

6.4 Morse CW Practice Mode
The AT 100M Pro includes a Morse CW practice mode. You can practice Morse code using the single paddle electric key function by operating the buttons on the front panel or by connecting an external 3.5mm single propeller key to the dedicated jack.


7. Maintenance
- Cleaning: Use a soft, dry cloth to clean the exterior of the device. Avoid using harsh chemicals or abrasive materials.
- Battery Care: To prolong battery life, avoid fully discharging the battery frequently. If storing the device for an extended period, charge it to approximately 50-70% capacity.
- Storage: Store the device in a cool, dry place away from direct sunlight and extreme temperatures.
8. Troubleshooting
- High SWR after tuning:
- Ensure all antenna connections are secure and correct.
- Calibrate the SWR value of the device when using it for the first time or after changing the radio. Refer to the instruction manual for detailed calibration steps.
- Check if the antenna is suitable for the operating frequency. - Device not powering on:
- Ensure the battery is sufficiently charged. Connect the USB Type-C cable to charge.
- Verify the power switch is in the 'ON' position. - Inconsistent tuning results:
- Ensure the device is placed on a stable, non-conductive surface.
- Check for any nearby metallic objects that might interfere with antenna performance.
9. Specifications
| Feature | Description |
|---|---|
| Model | AT 100M Pro |
| Material | Aluminum Alloy |
| Supported Radio | Any Radio |
| Supported Antenna | Any Antenna |
| Frequency Range | 1.8 - 30 MHz |
| Power Range (1-18MHz, SSB, CW) | 0.1W - 100W (Maximum 150W) |
| Power Range (18-30MHz, SSB, CW) | 0.1W - 50W |
| Power Range (1-30MHz, FM, AM, FT8) | 0.1W - 50W |
| Maximum Capacitance | 3869pF |
| Maximum Inductance | 17.21uH |
| CW Key Jack | 3.5mm |
| Charging Port | Type-C USB 5V 1A (Supports Overcharge and Overdischarge Protection) |
| Battery | Rechargeable Lithium Battery 3300mAh (Built-in) |
| Shutdown Current | Approx. 15uA |
| Standby Current (No Tuning) | Approx. 13mA, Approx. 150-200 Hours Standby |
| Standby Current (Tuning) | 130-330mA (depending on relays), Approx. 10-25 Hours Standby |
| Charging Time | Approx. 4 hours for full charge |
| Product Dimensions | 6.06"L x 2.91"W x 1.14"H (154mm x 74mm x 29mm) |
| Item Weight | 1.08 pounds |
| Manufacturer | WALFRONT |
| Item Model Number | WALFRONTzy7g81d0he |
10. Warranty and Support
Specific warranty information for the Walfront AT 100M Pro is not provided in this manual. For warranty claims, technical support, or service inquiries, please contact the retailer or manufacturer directly. Keep your purchase receipt as proof of purchase.





