Return to KLUBNL.PL main page

rsgb_lf_group
[Top] [All Lists]

Re: LF: WSPR - G0NBD

To: [email protected]
Subject: Re: LF: WSPR - G0NBD
From: "Johan H. Bodin" <[email protected]>
Date: Thu, 29 Jan 2009 10:26:16 +0100
In-reply-to: <3692CCEF55434A78A271B29E8D4BC318@JimPC>
References: <00c701c9818b$2aac4520$6401a8c0@asus> <16976E02F609403791409C408C93AFCA@AGB> <3692CCEF55434A78A271B29E8D4BC318@JimPC>
Reply-to: [email protected]
Sender: [email protected]
User-agent: Thunderbird 2.0.0.19 (Windows/20081209)
James Moritz wrote:
> Eventually, I realised that the
> difference was that your transmissions are a few seconds shorter than
> the locally generated signals


Dear Jim, LF,

that is a clear evidence of a soundcard sampling rate error. I am quite sure
that all timing in the WSPR software is derived from the sampling frequency and,
if memory serves me, the WSPR program uses a sampling rate of 12kHz. If the
soundcard does not support this rate and/or has a "physical" sampling rate that
is not a multiple of 12kHz (for example 44.1 kHz), then the driver or window$
will kick in a "resampler" between the soundcard and the WSPR application which
is asking for 12kHz. Many such resamplers are known to be inaccurate...

73
Johan SM6LKM


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