deCONZ cannot connect to RaspBee

I used a RaspBee for years on a Raspberry. It quit working and I struggled a lot to get it going again without success. So I started from scratch by downloading the stable image and wrote it to a clean SD card. But I got the same problem. It is in the connect to device dialog. But it cannot connect.
In the Help->Debug window [INFO] I get lots of this:
12:20:55:939 start reconnect to network
12:21:01:191 try to reconnect to network try=1
12:21:06:440 try to reconnect to network try=2
12:21:07:026 dev /dev/ttyAMA0 (/dev/ttyAMA0)
12:21:11:439 failed to reconnect to network try=3
12:21:16:440 failed to reconnect to network try=4
12:21:21:022 dev /dev/ttyAMA0 (/dev/ttyAMA0)
12:21:21:440 failed to reconnect to network try=5
12:21:26:439 try to reconnect to network try=6
12:21:31:439 try to reconnect to network try=7
12:21:31:992 dev /dev/ttyAMA0 (/dev/ttyAMA0)
12:21:36:440 failed to reconnect to network try=8
And continuing endlessly.

It did try to connect another port, /dev/ttyS0 if I remember correctly. But after I tried some of the things I found here, that changed. Something in raspi-config and the /boot/config.txt.

If it makes it simpler, I can re-flash the SD card to start with a clean slate if there is an installation instruction that works somewhere. The hardware is Raspberry Pi 3 Model B rev 1.2 and RaspBee no roman number, so I suppose first version.