I had real trouble getting a fix (nRTK, got a signal for the corrections ok) on a site today, on top of a hill with wide open skies. Occasionally got 1 engine fixed. I went home after giving up, and tried it in my garden, which has lots of trees around, and 6 fixed engines immediately. What was on the top of a hill about 200m away, was a large antenna tower. It looks more than just a mobile phone tower, but I don't know its exact function. Has anyone else had trouble with nearby towers? Is there a way to tell if my receiver is getting interference from this thing? Would the "New Options" mentioned on the website help with something like this?