Hi, everybody,
What a great thread, this one pertaining to alleged CW waveform
anomalies in certain Ten Tec transceivers. I am at a huge disadvantage
with respect to the technical claims made by several esteemed members
of the reflector, since my shack is out of service indefinitely while
we find a new house. However, it is my feeling that I can nonetheless
contribute a perspective from the metaphysical realm of CW operation
to the wealth of thought already presented.
In Paul Christensen's most recent message, he stated, "...the two
modes [CW and FSK] sound different...because the FSK offset is well
above the knee of this filter's lower passband skirt, thereby
producing waveform and note that is subjectively more pleasing than in
the CW mode."
And I couldn't agree more. After all, one makes a *subjective*
judgment to evaluate a CW note for its quality. To most of us die-hard
CW enthusiasts, the CW keying is every bit as important as the tonal
quality of an SSB transmission. And like anything else, we all have
our keyed waveform preferences.
Paul has frequently commented on the mysterious characteristics that
made some operators' notes so amazingly powerful. My favorite
adjective of his is "bone-crushing". Can you imagine anyone describing
a CW note as "bone-crushing"? Yet, that is a very good description of
what can actually happen in the human mind which is copying such a
signal.
However, think of all of the factors that have to be in place for you
to perceive the note as such. All of you have already named them:
transmitter ALC, BFO, and switching, receiver bandwidth, filter type,
group delay and shape factor, loudspeaker or headphone response. Given
the many opportunities for distortion, it is amazing to me that
amateurs can classify a signal as good or bad. But we can, and do. So,
why are we surprised that the same CW note can be perfectly okay with
one fellow and "an embarassment" to another?
What if somebody came out and told you that he actually liked the
little chirp, click, ringing, or whatever-you-want-to-call-it that old
crystal-controlled CW transmitters produced? What if, psychologically,
it made him feel as though he were being picked up off his comfy chair
a few inches and dropped back down every time the transmitter keyed
down, or that he got a pleasant tingling sensation at the back of his
head between the ears, or that somehow he could copy
crystal-controlled signals five words-per-minute faster than his usual
speed? In this case, the operator would actually *want* the
"anomalies" of the signal to stay there, even if he couldn't actually
articulate what it was about the signal he liked. He might say, "Well,
I don't have a spectrum analyzer like you do, and so I don't have any
measurements to back me up, but I can tell you subjectively that, for
some reason, I LIKE that signal!"
Is the Omni VI's leading edge too hard, just right, or not hard
enough? Is there really a chirp, and if so, is it objectionable, or
does it inexplicably make the note better?
There very well may be objective answers to these questions. In the
meantime, let's not let it bother us too much. The new members among
us, especially, must make sure there is really something there to
worry about before becoming completely discouraged by the discussion.
A final thought, which I can't claim credit for (thanks, Dad): If one
were to listen to the fifteenth harmonic of his 160-meter Omni VI CW
note on 10 meters, would the alleged chirp be any more apparent?
Theoretically, if there is 100 Hz of chirp on 160, it would become 1.5
kHz on 10 meters. Even I could hear that, I think.
R,
Al W6LX
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