My scope has 200 MHz bandwidth and can sample at 4GS/s
I'm sampling a 138 MHz RF signal at 500 M Sa/s storing 14 M points.
When I plot the spectogram in matlab I get the following spectrogram(Data,12000,8000,,fs,'yaxis')
While the signal does show up at 138 MHz, there appear to be aliases at 50 MHz, 190 Mhz and complex conjugate aliases at 86 MHz, 172MHz and 224 MHz. Does anybody know why this could happen?