Specifications:
Permissible Power Supply Voltage Range: 10–15V DC
Maximum Current Consumption: 500mA
Typical Current Consumption: 200–300mA
Maximum Operating Power: 150W
Maximum Measurable Power: 300W (SSB mode)
Recommended Operating Power: ≤250W (SSB mode); ≤150W (CW, FM, RTTY)
Minimum Power Required to Start Tuning: 8W
Minimum Measurable Power: 0.1W
Measurement Increment at ≤10W: 0.1W
Measurement Increment at >10W: 1W
Power Measurement Accuracy: ±10%
Maximum Installed Inductance: 8.53μH
Minimum Inductance Step: 0.05μH
Maximum Installed Capacitance: 1869pF
Minimum Capacitance Step: 10pF
Frequency Range: 3.5MHz–54MHz

Features:
1.Versatile Power Handling
Designed to manage up to 300W in SSB mode and accommodate various operational power levels, including CW, FM, and RTTY modes, ensuring compatibility with diverse transmission styles.
2.High Precision Tuning
Adjusts inductance in fine 0.05μH steps and capacitance in 10pF increments, offering precise control for optimal matching to your antenna system and minimizing signal loss.
3.Wide Frequency Range
Covers 3.5MHz to 54MHz, catering to amateur operators across HF and 6m bands, making it suitable for both long-range and local communication needs.
4.Lightweight, Compact Design
Weighing just 0.6kg, its portable construction allows convenient use in field operations as well as compact storage in indoor setups.
5.Reliable Power Detection
Starts tuning at only 8W and measures power accurately with ±10% precision, ensuring dependable performance for both low-power and high-power applications.

Usage Instructions:
* Before use, the antenna tuner must be properly grounded. Connect the RF input of the tuner to the RF output of the shortwave radio using a RF cable.
* Connect the RF output of the tuner to the antenna (it is recommended to install the antenna at a height of 3-6 meters above ground and use a 7-22 meter long wire with a cross-sectional area of at least 4mm². For installations at higher elevations, protection measures such as For rods are advised).

* Plug in the tuner's power supply (12-15V DC, usually shared with the shortwave radio).
* Turn on the shortwave radio and the antenna tuner. The device will perform a self-check and display status.
* Tune the shortwave radio to the desired frequency. Set the operating mode to AM, FM, CW, FT8, RTTY, or other modes that provide a continuous carrier signal. Press the transmit or CW key on the radio to initiate transmission at a power level of 8-15W. At this point, the HamGeek antenna tuner will begin automatic tuning. When the standing wave ratio (SWR) drops below 1.5, the tuner will automatically stop tuning. You should then stop transmitting. At this point, on the current frequency, you need to switch the shortwave radio to the intended operating mode, and then it can transmit at high power. When switching frequency bands, the tuning process must be repeated.
* If the tuner fails to achieve an SWR below 1.5, press the TUNE button to reset the tuner and repeat the tuning process. If tuning still fails, the impedance of the antenna feed system may exceed the tuner's tuning range, or grounding may need to be checked.
* If the tuner does not initiate tuning, check the following:
** All M-type cable connections are secure
** The tuner is set to automatic mode
** The radio is set to a mode that provides a continuous carrier
** The transmit power is sufficient to trigger tuning (must be over 8W but not exceed 20W)
** The tuner is functioning properly

Attention:
* Do not transmit at high power if tuning has failed or if SWR is above 1.5 — this may damage the equipment!

TUNE Button:
* Triggers tuning in manual mode; resets tuning in automatic mode. You can switch the order of inductance (L) and capacitance (C) in TEST mode.
* Attention: By default, the antenna tuner is set to automatic mode before shipping.

Automatic Mode:
* The automatic operating mode offers users a unique opportunity to use the device without pressing any buttons or connecting any external controls.
* The HamGeek ATU-130C automatically performs antenna impedance matching without requiring manual input or indicators.
* The algorithm functions as follows: If the current SWR exceeds 1.3 and the value has changed (1.3-1) compared to the one recorded after the last tuning process, the tuning mode will be activated. This condition is typically met when switching frequency bands, which then immediately triggers a new tuning cycle.

Package Included:
1 x HamGeek ATU-130C Antenna Tuner