[Tango Echo Dog]

Can anyone help me with a query about Russian radars?
The PVO history refers to MRU-105 radars in the Moscow area by the end of 1941. Does anyone have any information about them? It is possible this is a mistransliteration because RUS-1/2 radars are referred to as EN-1/2 in the Google-translated account.
Also is it true that the SON-2 gun fire-control radar was a copy of the British GL Mk II. I seem to recall the Russians disputing this.