Have anybody seen anything as massive as this before (in this band)?
I am guessing it's NOT a neighbor that has gone mad and gotten 100 weather-meters (although I'm sure stranger things have happened

It doesn't appear to be a mobile transmitter, since the signals are very steady in power.
It hawks the whole band.
A minute-long youtube video: https://www.youtube.com/watch?v=Ry7yJT9rdqI