Re: LF: WSPR 2.0 is now available

[Andy Talbot <andy.g4jnt@googlemail.com>]

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

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2009/11/19 Johan Bodin <jh.bodin@telia.com>:
>
>  http://physics.princeton.edu/pulsar/K1JT/
>
>
> 73
> Johan SM6LKM
>
>
>