Return to KLUBNL.PL main page

rsgb_lf_group
[Top] [All Lists]

Re: LF: WSPR 2.0 is now available

To: [email protected]
Subject: Re: LF: WSPR 2.0 is now available
From: Andy Talbot <[email protected]>
Date: Thu, 19 Nov 2009 17:29:07 +0000
Dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=googlemail.com; s=gamma; h=domainkey-signature:mime-version:received:in-reply-to:references :date:message-id:subject:from:to:content-type :content-transfer-encoding; bh=a41Jhz7aLf372YbVDS3/KcCsiMoFtCSzobI9GSHANjw=; b=gcUqgQ/o+FvF6uUR0kpBJRxoi3MQMcDKX7uh9EgxsJekvzMeMUuZT/b0tMTVOoyNWb nlEmQoG8lwJ6RSzvDllmvrpdDo2TNseMIk6J6JmRHcSEDf8L37tqZfAeuIQGvzw2p1l4 sJWEcgJdMPfFfEOl6Gzipm620rL2fW0Bw3J/A=
Domainkey-signature: a=rsa-sha1; c=nofws; d=googlemail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type:content-transfer-encoding; b=MggknXRi2I+TbN4JMcuZ4wbUwKDHLOLkmdHVVHkLclBwUHVuoV1jquSIgajgq1P84Q vWgkW4Ez8Ed2vMHjCEr+b4qiFrPhJ87VwuMsCuLowtx8g2J+cwT0n9r0cUChdP1BADuX eg6K8ySfOyUoyaTOgwKPmk6s6NMSDqGbsKNdQ=
Domainkey-status: good (testing)
In-reply-to: <[email protected]>
References: <[email protected]>
Reply-to: [email protected]
Sender: [email protected]
It has a calibration procedure built in, but as far as I can make out,
is aimed at solving frequency offset / tuning errors.   I may have
missed something, but there seems to be no facility to calibrate  for
soundcard errors in the same way as WSJT does, which can affect symbol
timing .  As we found in discussion on theis reflector a year or so
ago.    Sample rate timing error is enough to destroy WSPR decoding
even when signals are strong.

May be wrong, and will go and re read the appendices associated with
calibration, but no mention is made, specifically, of soundcard
sampling rate error - only refrences to frequency error.
FOrtunately, as WSPR is designed around 12000Hz sampling, this is
rarely out by more than a few ppm in most modern cards.   See my
Column in the latest RadCom for some soundcard sampling rate
measurements - and how bad some are


Andy
www.g4jnt.com

This email has been scanned for damaging side-effects by the health
and safety police



2009/11/19 Johan Bodin <[email protected]>:
>
>  http://physics.princeton.edu/pulsar/K1JT/
>
>
> 73
> Johan SM6LKM
>
>
>

<Prev in Thread] Current Thread [Next in Thread>