AirPort provides a firmware option that allows you to turn a regular ExpressLRS transmitter and receiver pair into a bi-directional transparent serial data link, over the air. Which is like turning the ELRS device into Xbees. We can set up a pair of ELRS AirPort devices to transmit the MAVLink command between the ground station and the air. Also, the AirPort has the advantage of a cheaper price and a longer effective range of communication. Cheaper and better, that is why we use it.
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By plugging RadioMaster Ranger into power and waiting for 60 seconds, the devices would enter WIFI mode. For Ranger, this can also be achieved by long pressing the middle button and switching the mode to WIFI mode.
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In the Web UI, you should see the firmware version of the device is to be v3.3.0-RC1 or any firmware version you just flashed to it. Under OPTIONS, the most critical setting for the airport is to check the box of Use as AirPort Serial device. Set up the baud rate of AirPort UART baud.
A good baseline is:
100Hz Full Res at 4800 baud for 868/915MHz
333Hz Full Res at 14400 or 9600 baud for 2.4GHz
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The Web UI also provides the option for the user to customize the function actions of the buttons. The picture shown below is the default setup of the buttons.
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Step 4 - Configure RX AirPort on Web UI
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The RX module should have the same ELRS firmware version, the binding phrase, and the UART baud rate as the TX module with Use as AirPort Serial device enabled.
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Then, go to the MODEL page. Making sure the Serial Protocol is set to CRSF. Otherwise, the AirPort won’t work!
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