In article ,
Rick wrote:

Every evening on 3865 here in the northeast US there is what I believe to be
a digital broadcaster.
The "noise" is a rasping sound, and it goes on all evening long, steady.
Quite strong.

I know nothing about digital reception. Is there a way to decode this
signal, by using my PC sound card and some software?

Try:
http://n1su.com/windrm/ (ham-oriented)
http://drm.sourceforge.net/ (broadcast-oriented)

The wide-bandwidth (broadcast-oriented) DRM systems may require that
you have access to a low-frequency-IF version of the signal, or tap
out a 455 kHz IF and mix it down to around 10-15 kHz.

I believe that the narrow-bandwidth (ham-oriented) versions could use
the audio output from a SSB receiver.

--
Dave Platt AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior
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