mkresin:

Versions LEDE 17.01.4 and Openwrt 18.06.0

I highly doubt it's an image provided by us. ra0/ra1 rather sounds like you are using the proprietary ralink driver for wireless, which neither OpenWrt nor LEDE uses.

Could it be that you're using the OpenWrt based firmware from ZBT?

jkimmel:

Yes, I'm using the OpenWrt based firmware 17.01

But you're right the correct terms are Generic MAC80211 802.11nac (radio0) and Generic MAC80211 802.11bgn (radio1) instead of ra0 and ra1

jkimmel:

If I could I would change in title Ra1 to radio0

jkimmel:

Sorry I got it wrong once more. It is radio1 breaking the device

jow-:

Provide dmesg, logread, /etc/config/wireless and ideally a serial log showing the crash.

jkimmel:

Despite first comment I got access via eth in 17.01.04
still crashing while accessing radio1 no traces left in serial log, not rebooting

Edit:
After scan via radio1 configured radio1 as client
Interface wwan was created and after reboot conection was established
Downloading ok, uploading immediate crash, rebooting