Same idea as seen here https://cryptomuseum.com/burst/index.htm
csi bcw.scm "AlPhAnUmErIc test StRiNg 012345678" - writes over burstCW.wav with encoded CW message.
play.sh # OF TIMES TO SLOWDOWN
slows down burstCWSlowed.wav given number of times and plays it back
i.e, "./play.sh 85" will slow burstCW.wav 85X in burstCWSlowed.wav and then play the resulting audio back.
To reverse a file: 'csi wavrx.scm file "in.wav" o "out.wav" reverse'
wavrx.scm file in.wav o out.wav [slow (# of times to slow sound)] [reverse]