I asked G3YYD how the stop bit measurement works. Since people might be
tweaking things it would probably be good to know what exactly we are
lookingand just as importantly what we aren't.
In summary, the stop bit length is determined by measuring the frame duration
from start bit to start bit and subtracting 6 bits (the start bit and 5 data
bits). 2Tone displays a running average of 8 characters with high/low thrown
out. So, it really shows you an average character rate assuming the data and
start bit average out to 22ms each (i.e., character spacing minus 132ms). I
doubt that it would show evidence of clock jitter like what EXTFSK can produce,
since that will almost certainly average out to look correct over 8 characters.
I hope that's helpful.
Andy K0SM/2
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