1. Introduction
The ATU-130 is an automatic antenna tuner designed for amateur radio equipment. It functions as a standalone device or as part of an amplifier or transceiver system, matching the output impedance of a power amplifier (PA) with the antenna feeder. This device incorporates a set of 7 inductors and 7 capacitors, enabling effective coverage of the wideband amateur shortwave range from 1.8 MHz to 50 MHz.
2. Package Contents
- 1 x ATU-130 Automatic Antenna Tuner
- 1 x Power cable (DC barrel jack to bare wires)
- 1 x Banana plug
- 4 x Adhesive feet
3. Setup
- **Grounding:** Ensure the antenna system is properly grounded.
- **RF Connections:**
- Connect the RF output of your shortwave transceiver to the "IN" port of the ATU-130 using a radio frequency cable.
- Connect the "ANT" port of the ATU-130 to your antenna.
- For optimal performance, it is recommended to install the antenna at a height of 3-6 meters above ground with a length of 7-22 meters. Implement lightning protection measures for antennas installed at high elevations.
- Connect the antenna's ground wire to the "GND" terminal on the ATU-130.
- **Power Connection:** Connect the provided power cable to the "DC 12V" input of the ATU-130. The power supply should be 10-15 VDC with a positive center pin. This power source can often be shared with your shortwave transceiver.
- **Initial Power On:** Switch on the power to your shortwave transceiver, then switch on the power to the ATU-130. The device will perform a self-check, and the OLED display should show normal operation.
4. Operating Instructions
- **Automatic Tuning Process:**
- Set your shortwave transceiver to the desired operating frequency.
- Select a continuous carrier mode such as AM, FM, CW, FT8, or RTTY.
- Press the shortwave transceiver's transmit button or CW key to initiate a continuous transmission at approximately 10W power.
- The ATU-130 will automatically begin tuning. Once the Standing Wave Ratio (SWR) is below 1.5, the tuner will automatically stop tuning and the transmission can cease.
- At this point, the ATU-130 is tuned for the current frequency. You can now switch your shortwave radio to your desired operating mode and transmit with high power.
- **Frequency Band Changes:** If you change to a different frequency band, the tuning operation must be performed again to ensure optimal SWR.
- **Manual Retuning:** If the SWR does not reach below 1.5 after the initial automatic tuning, press the "TUNE" button on the ATU-130 to reset the tuning process. Repeat the automatic tuning steps until the SWR is within the acceptable range (below 1.5).
Important Note: Never transmit with high power if the antenna is not tuned or if the SWR is above 1.5, as this may cause damage to the equipment.
5. Troubleshooting
- **Tuner Fails to Tune (SWR > 1.5):**
- The impedance of your antenna feed system might be outside the tuning range of the ATU-130.
- Verify that your antenna system has proper grounding.
- **No Tuning Action from the ATU-130:**
- Check all cable connections, especially to the "IN" and "ANT" ports, ensuring they are secure.
- Confirm that the ATU-130 is in automatic mode (if applicable, though the description implies it's always automatic when triggered).
- Ensure your shortwave transceiver is set to a continuous carrier mode (AM, FM, CW, FT8, RTTY, etc.).
- Verify that the transmit power from your transceiver meets the minimum trigger condition (more than 5W) for the tuner to start.
- Inspect the antenna for any faults or damage.
6. Specifications
| Feature | Specification |
|---|---|
| Supply Voltage Range | 10-15 VDC (center positive) |
| Maximum Current Consumption | 500 mA* |
| Maximum Working Power | 150 watts |
| Minimum Power to Start Tuning | 5W |
| Minimum Measurable Power | 0.1 watts |
| Measurement Accuracy (≤ 10W) | 0.1 watts |
| Measurement Accuracy (> 10W) | 1 watt |
| Maximum Installation Inductance | 8.53 μH |
| Minimum Inductance Step | 0.05 μH |
| Maximum Installed Capacitance | 1869 pF |
| Minimum Capacitance Step | 10 pF |
| Typical Consumption | 200-300 mA |
| Dimensions (L x W x H) | 155 x 88 x 38 mm (excluding protrusions) |
| Weight | 0.45 kg |
| Certification | RoHS |
*Note: Maximum current consumption is 500 mA.
7. Maintenance
To ensure the longevity and optimal performance of your ATU-130, follow these general maintenance guidelines:
- Keep the device clean and free from dust. Use a soft, dry cloth for cleaning.
- Avoid exposing the tuner to moisture, extreme temperatures, or direct sunlight.
- Ensure all connections are secure and free from corrosion.
- Do not attempt to open the casing or perform internal repairs, as this may void any potential warranty and could damage the device.
8. User Tips
- **SWR Meter Placement:** If you use an external SWR meter, it should be placed between your shortwave transceiver and the ATU-130's "IN" port to monitor the SWR presented to the tuner. The ATU-130 itself will then optimize the SWR for the antenna.
- **Low Power Tuning:** Always perform tuning at the minimum required power (5W) to protect your equipment. Only increase power after a successful tune (SWR < 1.5).
- **Antenna System Integrity:** A well-matched and properly installed antenna system, even before tuning, will generally result in faster and more efficient tuning by the ATU-130.
9. Warranty and Support
For information regarding warranty coverage, technical support, or service, please contact your original point of purchase or the product manufacturer, HLFEC. Keep your purchase receipt as proof of purchase.
