30 Jan
2014
30 Jan
'14
1:06 a.m.
Yes, and it
has nothing to do with Nyquist because the sample rate
you receive is only 2MHz or so as per normal. Direct sampling mode
does not capture a wider band than normal, it just uses a different
method to tune the receiver. So the oscillator frequency is
irrelevant, and Nyquist doesn't come into it any differently with
direct sampling than with normal sampling.
Mmm, AFAIK, the rtl ADC work at 28.8 MHz and then the IF tuning is
done by an internal digital DDC (which will also decimate down to 2MHz
or so to ship via usb).