3dr + APM2

Hello guys! 

I have a problem regarding the 3dr radios (433MHz) as they both can accept AT commands and strangely also accept RT for the air module. Strangely due to my problem. Both units are lined up with identical parameters(as you can see in the attached picture). I experimented a bit and came up with the following: When the distance is is < 3meters i am able to contact and send commands to the air module and the LEDs indicates a good connection(ground unit's red LED flashes VERY faint exept for connection established through 3dr radio tool). And if I turn down the Tx strength on both units to

5-8 the connection gets lost and I can only re-establish the connection with a distance less than 5cm.

Meanwhile they have connection with a Tx set to 20 and confirmed communication by RT commands, It is still impossible to get a data feed as I do without problem with APM2 in direct USB connection using the latest ADM Planner. Both units + APM2 is flashed through the APM Planner. Got an idea before i ship theese two 3dr babies all the way back to USA from nothern europe?

Rest of my system is a kit from event38

Best regards Jakob

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  • I bought the 915MHz 3DR radios and I am having the same problem.  The ground and air radios link together and I can run mission planner 1.0 with the the APM2 using the USB cable but when I disconnect the USB cable and connect the telemetry cable to the telemetry port and try to connect to the APM2 with the radio link through mission planner the countdown timer goes the whole way to o and times out with no heartbeat packet received.  I hav checked the serial port baud rate in APM2 and it matches the radios.  Don't know what else to do.  Have reflashed both radio units and the settings match but no luck getting the telemetry info through the radios back to the PC.  Everything works OK through the USB cable.  I will have to send the radios and possibly the APM2 back to 3d robotics if I cannot resolve this issue.  I am running windows 7 professional 64 bit software .

    Stan Pisarski


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