Ive been faced with similar problems over the years and especially when audio in and out rates differ. I know very little save using a couple of simple utilities to at least demonstrate what I have in front of me. We have some cal checks built in tests with the prog itself.....What to do about the offset results is another matter and James describes.
Ive been using the standalone Sound card calibration utility in MixW software http://www.mixw.net/index.php?j=downloads - its not to three decimal places but does visualize what the offset is for both In and out to the soundcard using a repetitive check sum. You can select the rate you have in the windows...
My Sound rate in is 8102.12 for a supposed 8000 rate....
I tried it today on my remote receiver up in Alaska just to check that I had both the rx cal and the sound card cal close enough (as I can get) and it seems to check out. It showed, after caling the sound card a 4.1Hz offset at 10Mhz using the non stab R75 up there and it was dead on...I havent tweeked that receiver for a year or too.
Im using standard cheap (Im presuming) Sigmatel C and Crystal something on one of the other ones. They arent that stable thats for sure....but good enough.
Laurence
> From: [email protected]
> To: [email protected]
> Date: Sat, 12 Sep 2009 13:33:07 +0100
> Subject: LF: Re: WOLF/WSPR Sound card issues
>
> Dear Dave,
>
> AC 97
> (http://download.intel.com/support/motherboards/desktop/sb/ac97_r23.pdf )
> specifies 48kHz as the basic, obligatory sample rate for compliant sound
> cards, so yours should certainly be able to do it - to find more info, you
> could try looking for the audio codec chip on the motherboard - usually a
> very tiny square 48pin thing near the audio connectors, and searching using
> its type number. But I guess what sample rate is actually used will depend
> on software, drivers and so forth - perhaps someone with experience of PC
> sound card programming could advise. Looking at the audio settings in the
> Windows control panel may well tell you what sample rates are possible.
> Also, some software allows you to select different sample rates, for
> instance Spectrum Lab, but not Argo as far as I know.
>
> The errors you are getting in the measured frequency seem to be enormous - 2
> or 3%, which would certainly give rise to problems.
>
> Cheers, Jim Moritz
> 73 de M0BMU
>
> ----- Original Message -----
> From: "Dave Sergeant" <[email protected]>
> To: <[email protected]>
> Sent: Saturday, September 12, 2009 11:59 AM
> Subject: LF: WOLF/WSPR Sound card issues
>
>
> It seems that both WOLF and WSPR are
> > designed for current sound cards which have 48,000 and 96,000 clock
> > rates. Mine is obviously from the old stable so has 44,100 etc rates.
> >
> > For information it is the sound card interface built into the
> > motherboard, an ASR Rock K7S41GX dating from 2003 with generic AC'97
> > sound. Zilch more given about its spec in the manual.
> >
>
>
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