marras

@jock at the end I was impatient and I cleared the emmc and tried to restore the backup... Everything went well, Android has been restored successfully! I think I was lucky because the backup is 2.5gb, under the fat32 limit, but after decompression it is as big as the all emmc (16gb). The problem is that I cannot extract anything from it, since the decompressed file is not an archive according 7zip, it's just a file without any extension. After cleared the emmc again, Linux from sd booted successfully and also after flashing in the emmc. wifi, hdmi works (only audio doesn't but I don't need that). I'm a bit disappointed by the performance, xfce doesn't run that fast, but it's ok since I need just to install klipper for my 3d printer and I hope it's enough for this purpose. Thank you for all the support, you have been precious!
 
 
 
 

Once you get a valid backup you can extract the dtb from the original image. But anyway I should already have a dtb for the t95n around.
 
In theory you should not even have the black screen if Android is still in the internal flash.
Normally Armbian on sdcard boots if it is already installed in the internal flash or the internal flash is just empty.
If Android is installed in the internal flash, the only thing that boots from sdcard is the multitool.
Then you can verify that the backups are sane (just open the files on a regular PC) and then may proceed to erase the internal flash to try armbian from sdcard.
You also have what I think are the serial pads if you have a serial adapter to connect for full boot logging.
 
The HDMI problem may be due to several reasons: incompatibility with your board, bad cable, bad monitor/tv, ... and the previous lockups during backups may be due to a bad power adapter for example (those coming with the tvbox are generally crap)