"Frank" wrote in message
news:01c386e0$9a92e3e0$0125250a@yludnifduhzssbbv.. .
... [SNIP]
Another advantage of Morse code is that several conversations can
simultaneously exist on a single frequency. Each station uses a tone
different enough to be distinguished by ear and an experienced operator
can
mentally filter out all but the tone he's copying.

This is not true.

If the "tone" is different at all, then the carrier is on a different
frequency.

Two (or more) CW transmissions on the same frequency will have the identical
"tone".

You can fit CW transmissions very close together, but not on the same
"single frequency".