View Single Post
Old October 4th 05, 08:04 AM
Floyd Davidson
external usenet poster
Posts: n/a

"Peter" wrote:

Amateur radio operators often use "c.w." as a kind
of informal short form for radiotelegraphy. It isn't
what it actually means.

Ahem... that is *precisely* what it means!

It actually means continuous
wave transmission as opposed to damped wave, or spark
transmission. Since damped vave transmission has
been illegal for nearly 80 years,

Exactly, and that of course actually means you cannot
modulate it...

You were doing fine until you got to this point!

all radio transmissions
of voice, data, television and everything else are c.w.

Nope, that just ain't so. They all require some form of
modulation that produces discontinuity of the carrier.

and the correct use of the term mainly appears in
historical discussions. If you use c.w. as a synonym
for radiotelegraphy, hardly anyone is going to object,
but if you try posting on a amateur radio newsgroup
that c.w actually means that, you are going to be corrected.
(And yes, it does happen.)

I think you need to look up the actual meaning of c.w., rather
than surmising on your own. You also need to realize that
c.w. is not defined by or for amateur radio operators, hence
references to what ham operators thing it does or does not mean
is only trivia.

I assure you the reason nobody (except perhaps a few ignorant
ham operators) objects to others equating cw with radio
telegraphy is because in fact it *is* a synonym for radio
telegraphy. (And be warned that I held a commercial radio
telegraph license 40 years ago, and still hold valid commercial
radio telephone and amateur licenses.)

Your statement that "all radio transmissions of voice, data,
television and everything else are c.w." is simply *wrong*.

Here is the technical definition of "continious wave", according
to the FTC 1037C Standards, available at

continuous wave (cw): A wave of constant amplitude and
constant frequency.

Clearly it means a transmission that is neither amplitude,
frequency, nor phase modulated. Any such modulation necessarily
must cause a discontinuity in the wave. The only thing you can
do is turn it on and off... which is called radio telegraphy!

The question, "when does improper terminology become
correct?" is very interesting. While I might personally
wish it never did, there is a perfect example of such
a thing happening in photography. Photographic emulsions
are not actually emulsions as chemists use the term,
and yet it is the standard term in photography. I imagine
that this must have annoyed more than a few chemists
who went into photographic chemistry. But no one has
managed to create a new word which conveys the same
idea to photographers, and so it gets used in scientific
papers where both the author(s) and the intended audience
know that it doesn't conform to proper scientific

My particular field of expertize is communications, not
chemistry. Hence I have no comment on this example, other than
hoping you know more about chemistry terms than you do about
radio communications terminology!


FloydL. Davidson
Ukpeagvik (Barrow, Alaska)