gr-scan is a program written in C++, and built upon GNU Radio, rtl-sdr, and the OsmoSDR Source Block. It is intended to scan a range of frequencies and print a list of discovered signals. It should work with any device that works with that block, including Realtek RTL2832U devices. I developed this software using a Compro U620F, which uses an E4000 tuner. That product doesn’t seem to be available on the US site, but the Newsky DVB-T Receiver (RTL2832U/E4000 Device) has good reviews. The current version of gr-scan is: 2012082301.
Download Link:- https://github.com/briand/gr-scan