From: DL4YHF@aol.com
Message-ID: <59.17194d45.2992c4c5@aol.com>
Date: Wed, 6 Feb 2002 12:41:25 EST
Subject: LF: PSK31, PSK08, Spectrum Lab
To: rsgb_lf_group@blacksheep.org
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<HTML><FONT FACE=arial,helvetica><FONT  SIZE=2>Hello Group,
<BR>
<BR>Thanks to all for the reports. Concerning PSK31 and PSK08:
<BR>In fact there is an implementation of PSK08 in Spectrum Lab, but it's not very user friendly and not really optimized (in fact, it is a crude version of PSK31 with two additional decimation stages before the decoder). I have compared its performance in the presence of white Gaussian noise and got a much lower error rate, but white noise is not a real world signal. 
<BR>So the practical "gain" of PSK08 against PSK31 in an LF-environment with static crashes and 'carrier type' noise and will be less. 
<BR>
<BR>In contrast to John's (G4CNN) observations, I did not notice missing or wrong characters in Jims transmission, the character error rate in his signal here in JO42 was less than one percent. This is certainly a result of the different types of noise at different locations, as digital transmissions with a "relatively high" symbol rate suffer much more from short crashes than others, and there is no error correction method in Peter's varicode set which was intended for fast keyboard-to-keyboard communications where it does an excellent job.
<BR>
<BR>(John, I hope you didn't use Spectrum Lab as a PSK31 decoder. It will not display a warning if the computer is not fast enough for a high-res waterfall and the PSK decoder running at the same time, so I highly recommend using one of the "profi"-programs like Digipan, WinPSK, etc etc. One of them may even have PSK08 implemented).
<BR>
<BR>If you want to do some experiments with the implementation of PSK08 in Spectrum Lab, you can download it from www.qsl.net/dl4yhf/spectra1.html . But beware ! The current version has the charm of a building-site (*), the proper function of the PSK08 decoder has not been verified since a long time and its almost certain that there are undiscovered bugs in it.
<BR>
<BR>(*) more about that soon, if other threads don't keep me busy.
<BR>
<BR>73, 
<BR> &nbsp;Wolf &nbsp;DL4YHF.
<BR>
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