Thanks to Wolf for your encouraging comments, and your work towards extending
the audio streaming utility to USB receivers.
I have been running the SMPS noise canceller in front of the colour-DF grabber
last night, and it seems to have pretty much
killed two of my nastiest noise sources. To faciliate testing, here is a
slightly different Windows-XP startup script. It offers
a wider passband centered around 1.5 kHz, and also creates the designated ..\dats subdirectory for the audio streams. After the
sound
utilities and the main program have started, you should be able to hear
cleaned-up audio from the soudcard. You can judge the effect
by pressing "b" to toggle bypass mode, or press "q" to quit. Any feedback is
highly appreciated.
Best wishes
Markus
----- Original Message -----
From: "Markus Vester" <[email protected]>
To: <[email protected]>
Sent: Friday, March 07, 2008 1:51 PM
Subject: LF: SMPS noise cancelling software
Dear LF,
as our LF and MF receiving is often plaguesd by intense hash from various
switch mode power supplies, I have tried to work towards
a software noise canceller, using estimation and subtraction. A short
description of the technique, along with free experimental
software and sourcecode, can be found on
http://members.aol.com/df6nm2/smps_nc/NC3F4.zip (63 kB). Hope you may find it
useful...
Kind regards
Markus, DF6NM
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