Observing the 21cm hydrogen line using a RTL-SDR DVB-T dongle and a cantenna:
▻http://lea.hamradio.si/~s53rm/Radio%20Astronomy.htm
http://lea.hamradio.si/~s53rm/Radio%20Astronomy_files/H-line%20cassiopeia-A.jpg http://lea.hamradio.si/~s53rm/Radio%20Astronomy_files/image010.jpg
#rtlsdr #radio #astronomy