[time-nuts] disciplining sound card
gary
lists at lazygranch.com
Fri Jul 6 21:13:22 UTC 2012
With an oversampled ADC (which virtually all soundcards use these days),
do you really know when a sample was taken?
For the traditional ADC that used a sample and hold followed by
successive approximation, you knew the moment of sampling. For MASH
converters, I'm not so sure.
For high accuracy spectral analysis, the 10MHz scheme should be better
than a stock soundcard.
On 7/6/2012 12:40 PM, Tristan Steele wrote:
> Another option is to do it yourself, it is one of my projects that is currently in progress. I have some early information at:
>
> http://electronics.ozonejunkie.com/category/electronics/time/10mhzaudio/
>
> I am aware that the jitter will not be all that low, but I was more interested in longer term stability. I have since made a smaller, neater board that just needs to go through some testing. If there is interest, I can post schematics up in the next few days.
>
> Tristan
>
> On 06/07/2012, at 20:13, lists at lazygranch.com wrote:
>
>> I'd suggest hacking USB type soundcards. It is certainly easier to get at the guts.
>>
>> There is a Chinese card peddled by a few vendors on ebay that comes in a blue metal case. You can slip out the PCB. The card uses CMedia chips.
>>
>> This is the first one I spotted on ebay:
>> http://item.mobileweb.ebay.com/viewitem?itemId=280506784055&cmd=VIDESC&index=19&nav=SEARCH&nid=33879388392
>>
>> I have an older version. These CMedia based cards work well under ALSA.
>>
>>
>> _______________________________________________
>> time-nuts mailing list -- time-nuts at febo.com
>> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>> and follow the instructions there.
>
More information about the time-nuts
mailing list