OK, I resampled that Alfred Hitchcock (Birds, get it? :-) sound clip
from Bill (actually from Tom) by a factor of two, and it has the same
structure as MFSK16.
I.e., when resampled by 2, it has the same tone spacing and bandwidth
and baud rate as an MFSK16 signal -- I took the sound file to a
laptop and used a music editor to resample and then piped the sound
through the headphones output of the laptop to a second computer that
runs the MFSK16 software.
If your computer can do this, you can try the same process and listen
to the resampled signal -- sounds just like MFSK16.
My MFSK16 decoder locks on to the signal's frames, but all I get is
gibberish so far, both on LSB and on USB. Might just need a longer
sound file for the Viterbi stuff to output proper bits from the FEC
and interleaver, who knows?
I don't have an Olivia decoder so I don;t know it this is just the
high speed Olivia.
I was hoping it was just sped up MFSK16 (like the way PSK63 is
created from PSK31) in which case the resampling step would have
created a printable signal.
But whatever it is, you can type twice as fast as you can on MFSK16,
unless there is s stronger convolutional code in the FEC.
73
Chen, W7AY
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