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PSK-31 Reality Check

Wow.  Here is a great Demo of Acoustical Phase shift!

I had PSK-31 running in diddle mode through the PC speaker so I could
capture the waveform for students on a Scope across the room.  As you
know this sounds like a pure tone with pure warble...

But each time I went to move over to the O'Scope to look at it, it sounded
like the PC started to send text!  But I went back to the PC, and it was
pure diddile.  I tried this several times, and each time I moved, I swear,
it sounded like someone began sending text.

Bingo!  The accoustic phase shifts by reflection from objects in the room
as I walked was introducing  phase shifts which sound identical to the
random phase shifts that occur in random text.

I'm sure someone walking by thought I was nuts as I walked about the room
shaking my head...  I can imagine now that with a pure diddle from a
speaker and a microphone on a moving platform, one could build a
mechanical maze that could actually spell something!

The biggest problem was the big echo reverberation between my ears

Anyway, it was an interesting observation that anyone can do...


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