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Old February 3rd 05, 05:18 AM
robert casey
 
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Michael Coslo wrote:

I felt kinda bad about being mean to Len, so I'll try to meet him
halfway with a Morse code topic. So maybe we can ressurect this old one...

I hear lots of Hams declare that Morse code is a binary mode.

It is most certainly not.

Let us look at the situation.

Is the Dit a "0"?
Is the Dah a "1"?

Is the space between characters a "0"? and the Dih a "1"? Oh wait, what
is the Dah then? Oh, and what about the space between words?


It's a form of pulse width modulation. Space between
characters would be a "low" or "0". Characters are
"high" or "1". A dit would be a single "1", dah would
be "1,1,1". Spaces between dits and dahs in the same letter
would be a single "0". Spaces between letters would be
"0,0,0". The typical letter is about 9 zeros or ones
long, and add 3 more zeros for the space on one side.
So the "1" or "0" bit rate is about 12 times the WPM
rate. 5 WPM would be 60 bits a minute, or 1 bit/sec.
20 WPM would be 4 bits/sec. Rather slow compared to
other machine readable/sendable digital modes, but
Morse can be read by ear and requires only simple
equipment. Big selling point back in the vacuum tube
radio era, but not so much today with high tech radio
equipment.