On Mon, 26 Apr 2004 21:27:45 -0400, Tom Rauch wrote:
>The problem is multiple, all rooted in the fact the PSK tone
>is fed into a low level audio port.
Thanks, Tom. That makes sense.
So it really isn't any different from the massive distortion we hear
during SSB contests when lousy operators (and lousy technicians) shove
way too much audio from their computers into the mic input of their
radio!
I just finished a PSK31 interface from my IBM T22 to my TS850. I'm
running my laptop sound card at full level, with a 20 dB pad at the
data input of the radio (it's a buffered input). Shield connections are
to the shell of the connector, which goes straight to the
chassis.Tthere's no connection to the so-called "audio ground," hence
no ground loop. A signal report from a local engineer looking on his
spectrum display is that it's clean. I haven't done IMD on it.
Jim K9YC
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