2013-03-09 Viewing the 2 meter band with a simple F ... 6 years ago
Viewing the 2 meter band with a simple FFT plot in gnuradio from the rtl-sdr receiver shows the entire band at once when I use 145 MHz as centerfrequency and 2.048 MHz as samplerate. This is a fun way to find activity in this band: soon APRS traffic (144.800 MHz) showed up and later simplex traffic on 145.3625 where I heard one end of the conversation clearly and nothing from the other person.Update 2013-03-10: At a different moment I let the same gnuradio companion script run for a while and made this plot. There seems to be a slight offset between the expected and the plotted frequency (such as 144.800), confirmed when listening to a receiver at the same time as watching the graph.
FFT plot from gnuradio from the 2 meterband