B LHG LTE6 it worked steadily for two months. At first it stood in the house in the attic and worked, then it was moved to the roof and also worked normally. Once it was decided to hide the wires well against the wall, since they were lying everywhere. The power was turned off and the wires disconnected, when everything was done, everything was connected in reverse order, but the microtyk started to reboot itself. Microtik-the Internet is there, but it is necessary to go to the site and the Internet disappears. PWR (always enabled) ETH, USR, LTE light up and go out, and it turns on for a while, that is, when you visit sites on your PC, it restarts and does not pass a minute.
1) if you select network mode only 3G, it does not restart and the transition to any sites works, only in this mode the speed is very slow.
2) if you select B3 the Internet is running a little longer, running Speedtest, it will restart again.
3) If automatic network search is selected and B3 Appears in the Primary channel list, and as soon as (Ca band B7 )will be found, restart again.
4) if you select B7, it will restart immediately and does not find the base station.

When everything worked, the operating system router was updated to a stable version and the modem firmware was updated to version: R11e-LTE6_V025, everything worked.

When did these reboots appear: 1) reset settings-did not help;2)updating netinstall, then to mipsbe-6.46.6 - did not help; 3) updating to beta-6.47 - did not help; 4)Replacement of the SIM card (though togozhe operator) - did not help; 5)Another cable-did not help (the cable length was 20 meters, but on a cable 2 meters long the same situation); 6)Another location did not help, mikrotik was in the suburbs, and now in the city and the same thing.

Everything is resolved thanks to a very quick support response, thanks =)
The problem was in the faulty power supply

Everything is resolved thanks to a very quick support response, thanks =)
The problem was in the faulty power supply

VERY GOOD.

I add some information. Some ppl insert to LHGR the LM940 etc. and reboot's starts because the Power Adapter is low power and we should use better PoE Adapter to recover stability.

PS. Thanks for giving a feedback !