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[email protected] · January 14th 07, 09:50 PM posted to rec.radio.amateur.policy

wrote:
From: (Michael Black) on Sun, Jan 14 2007
12:24 am

"Dee Flint" ) writes:

Most CW computer programs are set up so that for transmission you set the
radio to CW mode and then run a line from a computer serial port to the
straight key jack on the radio. Therefore you are using an actual A1A
transmission. Right off hand, I don't know any CW programs that feed a tone
into the mic jack although I suppose there could be some out there.

On the other hand, there was a time when some commercial SSB rigs
did use an injected audio tone to send CW. Whether or not they
actually sent A1 would have been determined by the purity of the tone
oscillator, and the carrier suppression and unwanted sideband suppression
of the sideband rig.

Most of the ready-built "CW" or SSB HF transceivers in use
today do that sort of keying.

If you mean they use a keyed audio tone fed into an SSB transmitter,
I think you are mistaken, Len.

Name some HF transceivers in use today that use a keyed
audio tone fed into an SSB transmitter as the way to generate "CW".

I don't think you can. I think you're just guessing.

Or maybe you intentionally imbed false statements in your posts as
a way of attracting attention to yourself....

Major reason is keeping the
PA at the same bias for all modes selected; makes for a
simpler mode selection control.

The same result can be had by using a carrier oscillator and keying one
of
the low level amplifier stages.

The first RTTY radio circuits,

"RTTY radio circuit" is redundant, Len, because the R in "RTTY" means
"radio".

It's like saying "PIN number" or "ATM machine". ;-)

A PROFESSIONAL writer would know that, I think.....

What happens at AF to RF translation in THIS group
is the emotional-baggage tie-in to the mythos of
morse such that direct RF on-off keying is somehow
a "pure way" to send "CW."

Those lost in the mythos
will contentiously state that audio tone generation
(with on-off keying of the audio) translated to RF
is "false" or "artificial."

Who, exactly, says that, Len?

Those folks just
haven't made the connection to spectral content of
ANY modulated signal...a few even contend that "CW"
(on-off keying) "has no sidebands" because "it is
just turned on or off!" :-)

As I have previously written, if you can't tell the difference on a
spectrum analyzer....

Perhaps worse is the group that believes
all-Class-C transmitters are "pure" in their
spectral content (as if those had no harmonics)!
Sigh... :-(

Who believes that, Len?

Class C amplifiers can certainly produce clean signals. They just need
the appropriate amount of filtering of their output to reduce harmonics
to an acceptable level.