Telemetry problems with tiny Module power

Hi all,

I’m having some problems to setup my system. I’m using PixHawk3 + HM-TRP telemetry modules.

Whenever I power the PixHawk 3 through the Tiny Module, telemetry on the Telem1 port stops.
However, this doesn’t happened if I ONLY power the Pixhawk through USB port.

This behavior is observed both using QGroundControl or screening on PC_Serial port (and also through blinking red light on HM-TRP module).

Px4 latest stable firmware is flashed through latest stable Ground Control, and other wise, everything seems to be working when connecting to QGroundControl on USB.

Latest, I cannot connect to PixHawk on USB console through the USB port as I could on PixHawk1. Serial communication is stablished but console it is not presented. Is this a normal behavior on Pixhawk3, or could it be related to the same problem?

Thanks very much for your attention. Any help is greatly appreciated.


Hi all,

Still having this problem with Pixhawk and Px4.

When I power the system through the USB port (using a usb power bank for example), telemetry works, I can see solid green light in both radios and blinking red light indicating data transfer, and QGroundControl connects with the Pixhawk3.

As soon as I connect an external battery pack to the Tiny Power Module, telemetry stops, both radios stay connected with solid green, but red light stops blinking and QGroundControl is disconnected.

Same problem happens if I only power the system from the Tiny Power Module on Power1/2 power ports. Radios are linked with solid green, but no blinking red light indicates no data transfer.

Does someone have a clue about this?




Can you measure the voltage on the output of the tiny power module please?


Sorry for the delay.

Measured voltages:

LiPO 11,61v --> QGroundControl reads (when connected through USB) 11,58v
TinyModule --> 5.19v (open circuit), 5.14v while powering Px3 (measured with a voltmeter in the Px3 connector)

It doesn’t look like a power problem, does it?

Is there any proceeding in Px4 that is mandatory before telemetry starts and that I may be missing? (kind of arming the vehicle, all the sensors ready… etc)



The Power module seems to be ok. I don’t know what is wrong.
You can send us back the Pixhawk for testing if you need. You can contact us on our site.
Thanks for your understanding.

connect telemetry radio to telem_port 1 on FC and all is ok values of distance sensor is now seen in HUD
in paramlist telem2 is compangion computer!!