[Hackrf-dev] 5 MSPS sample rate

[Michael Ossmann]

On Fri, Aug 02, 2013 at 12:06:08PM -0400, Russell Hande wrote:

>

> Mainly specs I think. I use 1, 2, 4 and 8 (8 is the min spec).

> 

> Going under the spec actually provides the best stability and least

> noise.


I suspect that is because the ADC is performing poorly when
underclocked.  You may be unintentionally filtering the signal by doing
that.  So there may be less noise, but there also may be less of the
signal you want.

While we currently allow you to operate the ADC below spec (which is 7.5
Msps minimum), the performance probably gets worse the lower you go.  In
the future we will implement decimation in the ARM, permitting lower
effective sample rates while operating the ADC within spec.  (See the
issues list.)