[Icom] PSK31 and sound card question.

Fri, 22 Mar 2002 13:43:13 -0500

Chris, good point! 
Just wondering why DigiPan works great and all WINPSK.DLL programs (WinPSKse and dx4win) do not receive well?
I just get garbage with all WinPSK.dll aplication programs.
Just trying to figure out why?
regards,
John
K1JEB

> -----Original Message-----
> From:	Chris Smolinski [SMTP:[email protected]]
> Sent:	Friday, March 22, 2002 1:32 PM
> To:	[email protected]
> Subject:	Re: [Icom] PSK31 and sound card question.
> 
> [email protected] wrote:
> > 
> > I use a compaq PC with a built in sound chip ESS Technologies ES1869F.
> > It is supposed to run of a 14.31818Mhz clock. When I measured the clock
> > input to the sound chip I measured 14.31954Mhz using a frequency counter.
> > 
> > The problem I have is, I have garbled text displayed even on strong signals.
> > 
> > How important is the clock frequency accuracy for receiving PSK31?
> > The clock on this board is difficult to tell where it is generated as I can not
> > find any 14.318  crystal oscillator. I'm tempted to unsolder the X0/X1 sound chip
> > clock input/output pins and build an off board crystal oscillator with
> > higher precision.
> 
> 14.3... MHz is a standard clock frequency found on the PC AT bus. It is
> probably derived from some other clock.
> 
> Assuming your freq counter is correct, you have a difference of around
> 95 ppm. For the [nominal] 1 kHz PSK31 audio carrier frequency, this
> would give you an error of 0.095 Hz after sampling. Is the SSB tuning
> precision on your rig superior to that? If not, this is a non-issue. 
> 
> 73
> Chris
> N3JLY
> ----
> Your Moderator: Dick Flanagan W6OLD, [email protected]
> Icom FAQ: http://www.qsl.net/icom/

--- StripMime Report -- processed MIME parts ---
multipart/alternative
  text/plain (text body -- kept)
  text/html
---