4.1 Beta [Dev Build] Issues


I have updated to 4.1 Beta and have come across a couple of issues;

  1. When using the VTX control, it is working however the mw in the OSD is not accurate. It states that is set to 25mw, 200mw, 500mw and then 800mw. However the VTX I have has the following power setting 25mw, 400mw, 800mw and 1600mw. I can see the power going to correct levels on the vtx. How do I get the OSD to display the correct value? My VTX is an AKK Race Ranger

Here are my settings:

  1. When trying to download my log files using mavFTP, the transfer rate is incredibly slow. I was under the impression that the latest version of Ardupilot fixes slow mavFTP transfers however it does not seem to have resolved this for me.

Any help would be much appreciated.



I’ve also noticed log file downloads from MP are very slow. I’ve also noticed that the file sizes are about double what they were before on 4.0.7. Have you seen a change in file size?

Sorry, the VTX thing is not possible right now. It requires more code to interpret the power values that SA 2.1 sends, at the moment they are hardcoded to the settings for a TBS Unify Pro.

I have not noticed this actually as I am yet to fly 4.1 Dev, these issues were only seen on the bench. I will be flying today and will compare the file sizes. Yes it is pain for me as my FC is buried in my plane so access to the SD card to get access to the log files is troublesome. I will end up having to cut a little access hole in the side!

Thanks for the update Andy, I dont believe the Race Ranger is SA 2.1 though, I believe only TBS VTXs support 2.1? Maybe it would be better to have VTX power level (Pit, 1, 2, 3 ,4) for example instead of the mw. Also, a nice feature would be to have maximum power when armed and pit mode when disarmed.

Ive just returned from a flight and I notice that when I change from Pitmode to the next power level (200mw) the video transmission breaks for about 2-3 seconds, it did this on the bench also. Do you experience the same thing with the TBS unify pro?

This did not happen when using the LUA script VTX power setting change. It also does not do this in iNav. (with the same VTX)

mw is more user friendly and the spec is a bit of a mess even between SA 1.0 and SA 2.0. VTX_OPTIONS already allows you to switch out of pitmode on arming.

I’ve not seen this, it’s possible that the order in which commands are sent might provoke something - without having that actual VTX it will be pretty difficult to tell.

Thanks, it is almost as if the band / channel is changed briefly when the power is changed, which is why there is a loss of signal. I’m guessing here! When arming the power level for me doesnt change, it only changes when I manually set this using a dial / switch on the transmitter. Is the VTX Power option telling it what power setting to go to when its armed?

It has to because power level changes are ignored in pitmode

What do you have VTX_OPTIONS set to?

Right well that is the issue then. The Band and Channel then should be first thing it does before it goes into Pitmode.

I’m using VTX options = 1.

The documentation is a little confusing as it says option 1 is Pitmode until armed and 2 Pitmode when disarmed. Isn’t that the same thing?

No, until armed means once you arm it will come out of pitmode and stay that way even if you crash. When disarmed means that it will re-enter pitmode if you disarm / crash.