Topband: PSK-31

[Michael Tope]

----- Original Message -----
From: "Jim Brown" <jim at audiosystemsgroup.com>


> On Tue, 27 Apr 2004 09:22:40 -0400, Joe Subich, K4IK wrote:
>
> As the old saying goes, "it depends." In this case, it depends on where
> the sound card clips/distorts, how much RF you might have floating
> around your shack, and providing immunity to hum/buzz that might be
> flowing on the shield of the cable between your PC and your rig.
>
> 3% THD corresponds to the harmonics being 30 dB below the fundamental.
> Most sound cards ought to be at least that good unless they're at clip,
> especially if there's no load on them, and a rig is a high impedance
> load.
>

Seems like another useful thing to do would be to run your
VFO low in frequency relative to the station you are trying
to work so that the audio tones coming from your soundcard
out are all high relative to the SSB bandpass of your exciter.
Seems to me that this would help prevent harmonics of your
audio signal from ending up in your TX spectrum.

73 de Mike, W4EF.....................