"Sensor Lost" alarm

I’m getting this from my QX7 every now and then and I’ve noticed that my VBAT drops out on my handset and my low voltage alarm obviously doesn’t work. However, I still get an accurate readout on my headset. Are the voltage readings for my VTX on a different system to my Receiver? Would the problem be in my receiver?

My quad has changed a lot over the course of about 9 packs. SOOOO many crashes! My cheap and nasty 4k camera is lost to the woods somewhere. I hope to retrieve it in the winter when the grass dies down. One of the RX antennas is a bit dodgy…

Mistakes were made… field repairs ensued…

They pull the information from the same place the FC.
The VTX will show it direct from the FC into your goggles as is hard wired in.
The Rx will have to send that data over your RF link to the Transmitter.

As you mentioned one of your Rx antennas is a bit dodgy… maybe you have damaged it.

You can put your transmitter into Range mode (if it has it) and fly out (LOW AND SLOW) as see how far you get.
In Range Mode your Transmitter power is reduced ALOT if you can fly out to 30 meters in Range mode then your Rx and Tx are probably fine.

Or walk away from you quad… that way it wont crash if you go too far.

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Awesome info! Thanks

I’ll give that a go asap. Cheers

OK I think I’ve got this right (correct me if I haven’t) but using my Taranis QX7 paired with my R-XSR I should be able to select RANGE mode on the “Setup” page (next to BIND).

From there I can do a range test where the distance is cut down to 1/30th of the real time distance.
I’m pretty sure only one of my antennas is dodgy due to a kink and pinch on a hasty field repair to one of the antenna wires. I assume I can test this by leaving the quad in one position and testing the range at 90 degree points…?

Ill give it a whirl anyways.


You got it. :slight_smile:

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I performed the test above, which was awesome BTW, and found that one antenna was slightly worse than the other. I’m definitely going to change that out next opportunity.
I updated the firmware on the R-XSR too. Apparently the ‘Sensor Lost’ alarm is common, however that may not be related to the voltage error im getting. In any case the problem hasn’t returned.

A side note. During the updating of my Firmware I may have “accidentally” removed the EU firmware on my Rx and somehow accidentally done the same to my XJT transmitter.
Does ignorance hold up in court…?