Date: Thu, 31 Dec 2009 13:34:34 -0800 From: Larry Cochrane <lcochrane@..............> Subject: Re: Volksmeter WinSDR ADC Bits Setting
Hi Bob,
The VolksMeter's interface board always sends 24 bits of data to WinSDR. Since the
lower bits are just noise at higher sample rates I added the option to WinSDR to
allow the user to select less then 24 bits for both the non-integrated (raw data)
channel(s) and the integrated channel(s). Below is sort of a block diagram of the
data flow through WinSDR.
Raw Data Channel
|--remove lower bits->filtering->display raw data
--24Bits -->|
|--remove lower bits->highpass filter->integrate->filtering->display data
Integrated Channel
Regards,
Larry Cochrane
Webtronics
Robert Thomasson wrote:
> I'm confused about the ADC bit settings on my Volksmeter. Channels 1 and 2
> (raw data) have a box for setting the ADC bits and this of course makes
> sense to me. But then the integrated channels 3 and 4 also have a separate
> box for setting the ADC bits, which evidently can be different than the raw
> data channels. I *thought* that the ADC was done at the chip level and only
> once per channel? And that the integration on Channels 3 and 4 was done by
> the software on the raw data from Channels 1 and 2?
>
> I don't understand how the Channel 1 data could be at 20 bits and the
> Channel 3 data could be at say 24 bits? But they are evidently independent
> of each other. I didn't find any discussion of this in the documentation
> but if it's there could you point me in the right direction to find it? Or
> provide a brief explanation of how the ADC works differently for the raw and
> integrated data? Sorry if this is a dumbass question.
>
> Thanks,
>
> Bob Thomasson
>
.