Hello Graham,
Sorry for having to post this response on the reflector... the usual
annoyance with certain email providers.
Here is what your provider just "said" :
host mx4.hotmail.com [65.55.37.120]: 550 SC-001 (COL0-MC4-F14)
Unfortunately, messages from 195.4.92.92 weren't sent.
Please contact your Internet service provider since part of their network is
on our block list.
In other words, freenet.de is blacklisted by hotmail.com . Aargh.
Here is what I originally wanted to reply:
Of course Spectrum Lab cannot affect the sampling rate delivered by
Windows to another application.
The problem is, as so often, windows itself. It tries to be "very
helpful" when multiple programs use the same audio hardware.
The soundcard's A/D converter (hardware) can only run one sample rate.
This is ok as long as only one program uses it.
But when two programs try to use it, with *different* sampling rates
(especially when they are not integer multiples) some bad things happen
- called resampling. Windows does an extraordinarily poor job at this...
for example, it may decide that to deliver 11.025 kSamples/second to
application "A" and 48.000 kSamples/second to application "B", it's
guesswork at which sampling rate the ADC is actually run. (I often get
the impression that in these cases windows rolls the dice). It may be
48000 S/s, but then the 11025 S/s output will be difficult. It may also
be 44100 S/s, then the 11025 S/s output receives "every 4 th sample" (in
simple terms), but constructing the 48000 S/c output will require some
rather tricky (and poor-quality) fractional resampling.
That's why it's the operator's duty to configure all programs to use the
same sampling rate. 48000 Samples/sec seems to be a good choice these days.
Also all the best for 2012,
Wolf .
----
Am 30.12.2011 15:31, schrieb G ..:
Wolf ,
Over the last days , I have run tests with Jose , Ros , with
Speclab running on the same PC ,
During some qso's I noted Ros lost decode after a short time
with good signal level , after some repeats , I found that
,only when Speclab was running , was this problem.. I don't
think this is a new problem as I have some lock problems with
the Ros mode on MF , which could not be explained
Jose coded a test version of Ros and this showed that when
Speclab was running , then Ros needed to compensate the sample
rate ..the new test version then decoded 100% with Speclab or
without Speclab
Speclab was set to the default 11KHz or 12KHz sample rate ..
later I found that if SL was set to 48KHz or 41KHz then there
is -no- problem , so it seems to be linked to the low sample
rate setting's
Q
When the low sample rates are selected , 11 or 12 Khz , how can SL
affect the sound card sample rate ? ,
Jose tells me Ros needs 48KHz sample rate, Is there
something I have not set in SL set up ?
Many thanks , best for 2012
Graham
G0NBD
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