SCAF-1 Noise Filter Demonstrations
This page links to sound files in MP3 format. Most browsers will already be configured to play the sound files properly when the links are clicked.
If the sound files do not play properly when they are clicked, then you could try right-clicking on the link, and clicking “Save Target As…”, or “Save Linked Content As…” (or similar) to save the sound file on your computer, then go find the file you just saved and play it.
CW Sample File 1
In this file you will hear the filter, first switched out completely, then switched in, and then the cut-off frequency control being tuned from high to low.
CW Sample File 2
A brief file, copying CW. First, the filter is switched out in an environment with considerable line noise. The filter is then switched in. The filter does not claim to remove the noise, but it makes copying much easier and less fatiguing.
CW Sample File 3
A longer file, copying a CW signal that has some QSB, with some line noise. The filter is switched in and out multiple times. This file demonstrates very well the effect of also removing white noise.
CW Sample File 4
A brief file, showing first CW with no filter, then the filter switched in but at maximum bandwidth, then the filter is slowly “tightened” onto one signal.
CW Sample File 5
A brief file, showing CW first with a bad electrical noise, then the filter switched in. Again the noise is not removed but is considerably attenuated and copy becomes more pleasant.
SSB Sample File 1
A brief file, copying a fairly weak mobile SSB station, with background line noise. The apparent improvement when the filter is switched in does not seem huge, but the improvement in copy is substantial!
SSB Sample File 2
Another brief file of a signal with line noise, and the filter out, then switched in.
SSB Sample File 3
A brief SSB file, showing QRM reduction when the filter is switched in.
SSB Sample File 4
A longer SSB file, with the filter switched in and out several times primarily demonstrating QRM reduction.
SSB Sample File 5
A longer SSB file, again with the filter switched in and out several times primarily demonstrating QRM reduction.