Below is a comprehensive setup guide on how to program your Harxon external radio kit to broadcast baseline corrections over the 450 MHz Trimtalk™ protocol. Incorporating this high-power transmitter into your inventory significantly extends the operational field boundary constraints of the Emlid Reach RS3, fully utilizing its newly engineered internal receive-only UHF radio module. This integration path enables you to broadcast a powerful 35W transmit signal from either an Emlid Reach RS2+ or RS3 base station over to an RS3 rover layout.

Step 1: Hardware Assembly & Initial Connections

1. Assemble the high-gain external antenna array and secure it tightly to the radio frame mount. Connect your heavy-duty power and serial data combination cable to the base of the radio, then apply battery power to turn the unit on.
2. By utilizing the physical faceplate arrow keys and integrated LED screen panel, you can run straightforward adjustments to select basic configuration profiles.

⚠️ Technical Advisory: While the onboard screen layout handles basic channel switching, you must use the specialized desktop Radio Configuration Tool on your PC to explicitly program custom channel frequencies and legally encode your station's Call Sign properties.

Step 2: Desktop Radio Configuration Tool Setup

1. Plug your serial-to-USB utility cable into your PC workstation and launch the Radio Configuration Tool software. Click Connect and then select Read to ingest and populate the parameters of your radio’s current internal profile.
2. Systematically review the utility tabs to cross-check that all frequency thresholds match the exact boundaries specified on your business FCC license to guarantee strict legal compliance.

5. Review the input threshold metrics located under the Power Manager window block. Note that these specific safety values fluctuate based on the type and voltage rating of the external battery pack deployed to power your site setup.
6. Input the alphanumeric Call Sign matching the document records listed on your legal operator license. Click the Write action button to save the updated settings, then execute a hard reboot on the radio hardware to finalize firmware configuration steps.

Step 3: Configuring Base Output in Emlid Reach

Once the external transceiver is configured, link it to the base station file browser system. Launch your desktop web browser to access the local web interface panel by typing your specific base receiver name, followed by the network suffix in the main address bar: [Name of receiver].local

1. Navigate into the main Base output options tab.
2. Change your baseline transmission profile Channel parameter over to Serial.
3. Set the routing Port selection explicitly to USB OTG.
4. Configure the communication speed by matching your serial Baud rate exactly to 115200.

Step 4: Live Data Transmission

Connect the serial communication link cable between your calibrated Harxon unit and the data port of the base receiver. As soon as the base station resolves a stable Base marker coordinate point, the data pipeline unlocks.

The base receiver will immediately feed correction streams out to the high-power transmitter, causing the external radio's transmit status LED indicator light to flash a steady red pulse. This visual confirmation indicates that your long-range baseline correction mesh is fully operational.

⚠️ Legal Operating Notice: Programming your Harxon external radio to broadcast base corrections over the 450 MHz Trimtalk™ spectrum will instantly boost the long-range operations boundary of your Emlid Reach RS3 rover. However, be advised that transmitting over 450 MHz high-power commercial frequencies requires a valid radio station authorization license inside the United States. You can formally apply for and register your organizational call signs using the official FCC Universal Licensing System portal link above.