I came across an article back in June on using certain cheap Realtek RTL2832U based USB TV tuners function as general purpose software defined radio (SDR) receivers. Here are some of the features:
- Frequency range : 64 - 1700 MHz (50 - 2200 MHz also possible)
- Sample rate: 3.2 MS/s
- Resolution: 8 bits/sample
- < 4 dB noise figure1
- Software support: GNU Radio, Winrad, HDSDR, SDR# etc.
- Receivers implemented: AM/FM, GSM, P25, ADS-B, TETRA, GMR, GPS, etc.
I use SDR# which gives me Wide and Narrow FM filtering and its completely adjustable. I can decode 137 MHZ weather satellite imagery, 2 meter APRS with an AFSK 1200 decoder, can do NOAA Weather Radio DXing just to name a few things with mine and I have barely scratched the surface. I recommend looking at http://sdr.osmocom.org/trac/wiki/rtl-sdr It will give the particulars on which cards to use and are widely available on Ebay. You can also do a you tube search for RTL-SDR and there are some great videos on the capability of the cards. Lastly take a look at SDR# its the powerful free piece of software I use the addresshttp://sdrsharp.com/ They just added RDS decoding with the latest software build. At $20 you cant go wrong.