first things first. You need a reasonably powerful PC to do SDR on. As your running Windows 7, that may not be the case. What are the specs on your PC?. Secondly you need a reasonably good outside antenna. It would help if you post a screenshot of your waterfall when trying to receive a DMR signal as you need a clean signal also. Its best to start easy with just one signal rather than go full belt into scanning. Most guides miss out these basic requirements.