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Old January 16th 07, 01:00 AM posted to rec.radio.amateur.policy
Stefan Wolfe Stefan Wolfe is offline
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First recorded activity by RadioBanter: Dec 2006
Posts: 179
Default One way to promote learning of code ...


wrote in message
...
On Sun, 14 Jan 2007 23:46:39 -0500, "Stefan Wolfe"
wrote:


wrote in message
roups.com...
First let me say that, in amateur radio use, the term "CW", when used
to mean a mode of radio communication, is universally defined as "Morse
Code radiotelegraphy by means of an on-off keyed carrier". The literal
"continuous wave" meaning does not apply.

Stefan Wolfe wrote:
wrote in message
ups.com...

The big question is whether the signals (keyed carrier vs. keyed
audio
tone) look different on a spectrum analyzer. If they don't, why
should
FCC care?

I agree that it doesn't matter to the FCC as long is the keyed audio
tone
is
coupled to the radio with EM waves such as with light (optoisolators),
RF
or
wires (electrical connections).

However, if you couple the keyed audio carrier acoustically,
speaker-to-mike
using only sound waves, then that is J3E and only permissible in the
voice
portion of the band.

No, that's just not true - *IF* the rig and tone are clean enough.

Problems arise when the tone is not a pure sinusoid, or the transmitter
does not have adequate carrier- or unwanted sideband-suppression. But
that's
not what is being discussed here.

Feed a Morse-Code-keyed audio tone that is a pure sinusoid into an SSB
transmitter of sufficient quality, and the result is "CW".

It doesn't matter how the tone gets into the transmitter, as long as
the process doesn't introduce other tones or artifacts.

If I were to whistle nearly pure sine waves (I am a good whistler,
perhaps
you have seen paintings of my mother :-)) in Morse code into the mike
input,
it might look like CW and sound like CW but it would really be J3E,
hence
illegal in the CW sub-bands.

No, that's not true, unless the whistle isn't a pure sine wave.

Using acoustic coupling (J3E), it becomes a slippery slope; first
computer
generated tones, then human whistling, then humming and before you know
it,
"talking" (di dah di dah etc.. and finally, "words" :-))

Not a slippery slope at all. All that matters is what it looks like to
a spectrum analyzer. If the whistle is a pure sine wave, the output
will be a single carrier. But if it's not a pure sine wave, the result
will be spectrally different, and illegal.

From a regulations standpoint, it does not matter how the signal is
generated. What does matter is that it meets the standards of spectrum
purity.

Now you might argue that a simple "CW" transmitter using keyed Class C
stages and vacuum tubes can be much simpler, more electrically
efficient, and certainly more elegant than a newfangled
computer-SSB-transceiver-kluge-setup, yet deliver a signal of equal
quality. That's true - but it's a different issue.

I give up.


indeed you see his style of deabte evade nit pick and sidestepp avoid
anything

You keep talking about how the signal looks when it is
*received*. I keep talking about how the true A1A signal is supposed to be
*transmitted* (your last paragraph is exactly that but you dismissed it).
Part 97 is not concerned with how you receive, only how you transmit.


even the rules must yeld to "logic" of the ProCoders

I
agree it is true that you can fool anyone on the receiving end as long as
you can make the signal look like A1A on a spectrum analyzer. That might
be
difficult because the sidebands generated by breaking a CW "square" wave
would be present on my A1A transmission and you would somehow have to
re-create them on your SSB pure tone transmission that is keyed in your
tightly filtered audio circuit. But re-check the definition of A1A and
you
will see that there is only one way to *transmit* it. And A1A is the only
FCC definition of "CW". It is a moot point because tone generated data (as
a
sinusoidal "mark" in your SSB transmission) is legal everywhere that CW is
legal. The same is not true of the voluntary band plans. It it is
important
to know the difference, even if you think the difference makes no
difference
so to speak. And I said that whistling CW into the mike is J3E voice, not
A1A, and the only thing that separates it from being legal on the CW
sub-bands is the way the data is coupled, not how it is received or
transmitted. You completely missed all of my points.

he is very good at missing points

OTOH it is one of the more legit styles used by th e ProCode Luddites
on here
http://kb9rqz.blogspot.com/


Ummm....surprize, I am not/never was pro-code "test" but I think copying
code in one's head once in a while is a good mental exercise. Do you ever do
anything to exercise the mind? The physical analogue would be riding a
bicycle. It has value and can be enjoyable for some but I agree you should
not have to pass a bicycle riding test to get an automobile drivers license.

However, as a driver, I guess I would be slightly embarrassed if people
found out I did not know how to ride a bike ;-))