Video artefacts in DJI Go with HDMI module

[petr22]

Hi, does anyone experienced similar problem?

After installation of HDMI output module, there are artefacts in DJI Go which after a short while, almost preventing controlling Phantom drone, because it is not possible to see clear picture from camera. It look like communication over USB is not fast enough to transfer image data. It happen with two Android devices and all usb cables I have, therefore it should not be fault of Android device or cable. Picture displayed on HDMI output is crystal clear whole time, but it is not possible to control all functions using DIY FPV gogles. I doublechecked all flex cables inside transmitter and HDMI module and look like there is no problem there. USB debugging must be turned on, otherwise DJI Go is not able to connect to tramsmitter.

 

[BGecko]

You may be getting wifi interference thats causing bandwidth issues. Check the HD settings in the main menu and see if you are getting a lot of red bars. You may want to go to custom channel and set a channel that is stable. You can also bump the data transfer bandwidth up to 6Mbs.

I am experiencing something similar. We were testing the HDMI module and I was noticing a slight lag in the video. We have a lot of wifi interference and hopefully this is all it was. We are going to be broadcasting live this weekend and hopefully wont have the same issue.

 

[petr22]

Picture from HDMI output to FPV goggles is crystal clear, it does not look like image transmission problem to me. It look like problem with communication between transmitter and tablet over USB.
There should not be interference problem when drone is sitting next to controller in the middle of woods, at least 2 kilometers from nearest village.

I will try different channels and bandwith settings if it affect artefacts or not.

HDMI module look like generic DJI no 54 part with DJI logos all over the package.

 

[petr22]

There seems to be a problem with HDMI module itself.

I found a thread, where is recommended to downgrade firmware from 1.80 to 1.60 and upgrade it again with HDMI module inserted (my controller was updated without HDMI module). When version 1.80 was installed again, DJI Go show that firmware version is 1.60+ instead of 1.80, it does not allow to control Phantom and constantly display message that firmware upgrade is required, but it always fail, as it is already installed

 

[petr22]

After several try-it-and-test attempts with downgrade and upgrade of transmitter firmware I found the problem.

Main problem is, that DJI firmware 1.8.0 is not compatible with DJI own HDMI module.

When firmware in upgraded from 1.6.0 to 1.8.0 with HDMI module in transmitter, it shows that version is 1.6.0+ and does not connect or create video artifacts as shown on the picture, preventing controlling the aircraft using mobile device.

Downgrading transmitter firmware back to 1.6.0 solve the problem, version in DJI Go is 1.6.0 instead of 1.6.0+, aircaft connect instatnly to controller and picture is displayed without single artifact or corruption, with all bitrates from 3 Mbit/s to 10 Mbit/s.

Look like this problem is to DJI to solve it. DJI Go wants to update to 1.8.0, but is is no-no for me until problem is solved.

Firmware 1.6 is over 26 MB, firmware 1.8 is only 4 MB in size. It is not an download error, tried it several times, it always download 4 MB file.