One way to promote learning of code ...
 

"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.

Dee, N8UZE


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.

A more common occurance was RTTY, when AFSK was often used to send
FSK on an SSB rig. (I suppose it was more common since it was
easy to unbalance a balanced modulator and just key a stage for
an SSB rig, especially when it came from the factory that way, while
commercial rigs did not tend to have built in FSK ability and of course
frequency shifting often resulted in slight variation of how much shift
occurred depending what you modified and what you shifted. And of course,
it was easier to inject an AFSK generator into the sideband rig than
mess with frequency determining elements in the rig.) Nobody really
thought badly of this practice, so long as it provided a decent
sinewave.

LIkewise, SSTV always (well maybe not in recent years, I don't know)
be done by modulating an audio oscillator, and then feeding it into
the mic input of the SSB rig.

With good supression of the carrier, good suppresion of the unwanted
sideband, and a pure enough audio oscillator, the only thing that
would be noticed about the output signal would be that the dial
of the transmitter doesn't directly show the transmitted frequency,
since of course the carrier isn't being turned on and off, an audio
oscillator is so it provides an offset.

This is precisely why two-tone oscillators are needed for testing
SSB transmitters. Because only then are you actually modulating
the output. Otherwise, it's just a carrier.

Michael VE2BVW

A1A computer Morse on the AM commerical band
 

"Dee Flint" wrote in message
. ..


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.

Dee, N8UZE

Thanks Dee. I was thinking the situation was otherwise but I never really
looked into what people were actually doing with the hardware.

Here is a really simple A1A keyer for non-hams (it seems to be aimed at
kids) that ressurrects Morse and even encourages them to memorize it rather
than building a Morse decoder on the other end. You use it to transmit from
your serial port directly to the AM commercial band (10000 Khs) and the
other side listens on a commerical AM radio. Any guesses as to the range? I
suppose it is legal due the ultra low power. Yes, it is elementary...but
seems more like being like a "ham" than some of today's licensed amateurs
:-))

Other than enjoying high growth with the disabled, is the future of Morse
with young non-Ham experimenters?

http://sci-toys.com/scitoys/scitoys/...ansmitter.html

One way to promote learning of code ...
 

Stefan Wolfe wrote:
My reading would be, computer "CW" (with sound card output electrically
coupled to mike input and does not operate true A1A), is still legal in the
CW sub-bands provided the data coupling from computer to radio is electrical
and not acoustic.

Doesn't matter.

This would imply, of course, that computer programs for CW are not
acceptable (even if legal) across the entire CW allocation unless the output
actually "keys" the CW carrier. They are NOT equivalent to CW.

Yes, they are. Or rather, they can be.

If you have an ideal SSB transmitter, and you feed an ideal sine-wave
audio tone into it, you get a pure carrier output. Key the ideal
sine-wave audio tone, and you have a keyed carrier.

Now of course if the SSB transmitter or the sine-wave isn't ideal, you
wind up with unwanted outputs, such as the suppressed carrier or the
unwanted sideband. How much suppression is needed is another matter,
but I suspect that with modern methods the unwanted products could be
kept low enough not to make any difference.

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?

73 es KC de Jim, N2EY

A1A computer Morse on the AM commerical band
 

"Stefan Wolfe" wrote in message
...
You use it to transmit from
your serial port directly to the AM commercial band (10000 Khs) and the
other side listens on a commerical AM radio.
http://sci-toys.com/scitoys/scitoys/...ansmitter.html
Whoops, typo....S/B 1000Khz.

A1A computer Morse on the AM commerical band
 

"Stefan Wolfe" ) writes:
"Stefan Wolfe" wrote in message
...
You use it to transmit from
your serial port directly to the AM commercial band (10000 Khs) and the
other side listens on a commerical AM radio.
http://sci-toys.com/scitoys/scitoys/...ansmitter.html
Whoops, typo....S/B 1000Khz.


And wouldn't it be A2? Or have they tossed out that designation?

A2 was/is an audio tone into an AM transmitter.

It's what's used for the "code" function on all those old "no license
required" 100mW 27MHz walkie talkies with the code keys. It has
the advantage that you don't need a BFO at the receiver end.

ANd of course, there was that period in the US when the 2M phone
privilege went away for the Novice class license, but A2 continued
to be allowed, presumably because all the cheap AM transceivers had
no means of sending CW.

Michael VE2BVW

One way to promote learning of code ...
 

Jim wrote:
Stefan Wolfe wrote:
My reading would be, computer "CW" (with sound card output electrically
coupled to mike input and does not operate true A1A), is still legal in
the
CW sub-bands provided the data coupling from computer to radio is
electrical
and not acoustic.

Doesn't matter.

This would imply, of course, that computer programs for CW are not
acceptable (even if legal) across the entire CW allocation unless the
output
actually "keys" the CW carrier. They are NOT equivalent to CW.

Yes, they are. Or rather, they can be.

If you have an ideal SSB transmitter, and you feed an ideal sine-wave
audio tone into it, you get a pure carrier output. Key the ideal
sine-wave audio tone, and you have a keyed carrier.

....offset from the (nulled) carrier frequency, by the pitch of the audio
tone.
LSB: 7.025 MHz - 440 Hz = 7.02456 MHz.
USB: 7.025 MHz + 440 Hz = 7.02544 MHz.

Now of course if the SSB transmitter or the sine-wave isn't ideal, you
wind up with unwanted outputs, such as the suppressed carrier or the
unwanted sideband. How much suppression is needed is another matter,
but I suspect that with modern methods the unwanted products could be
kept low enough not to make any difference.

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?

And, for decades, it's been exceedingly simple to create a very low
distortion sinewave at audio frequencies. Prior to digitally synthesized
oscillators, the best known was (is?) a Wien Bridge oscillator:
http://en.wikipedia.org/wiki/Wien_bridge_oscillator.


73 es KC de Jim, N2EY

73, Bryan WA7PRC

One way to promote learning of code ...
 

"Stefan Wolfe" wrote:

"AaronJ" wrote in message

My programs both send and receive CW.

when using such programs,
does the radio actually transmit A1A does it transmit SSB with the analog
sound card output connected to the mike input?

I have never used the mike input for computer CW. My homebrew CW transmitters
don't have a mike input. I key the transmitter directly from a computer port
driving a keying relay. In my programs I use Basic POKE statements to access the
computer ports directly.

A1A computer Morse on the AM commerical band
 

"Michael Black" wrote in message
...
"Stefan Wolfe" ) writes:
"Stefan Wolfe" wrote in message
...
You use it to transmit from
your serial port directly to the AM commercial band (10000 Khs) and the
other side listens on a commerical AM radio.
http://sci-toys.com/scitoys/scitoys/...ansmitter.html
Whoops, typo....S/B 1000Khz.


And wouldn't it be A2? Or have they tossed out that designation?

A2 was/is an audio tone into an AM transmitter.

I think in this circuit pin 4 of the serial port connects to the power input
of the oscillator cihip. The oscillator 1MHz "carrier" is truely keyed on
and off, thus it is A1A.

One way to promote learning of code ...
 

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.

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.

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" :-))

One way to promote learning of code ...
 

"Stefan Wolfe" ) writes:
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.

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.

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" :-))


But it could never be A1, because it doesn't meet the criteria of a pure
tone into a good SSB transmitter.

I doubt however good a whistler you are, that you can guarantee it's a sine
wave and doesn't include any peripheral noise. And that microphone is bound
to pick up background noise, so you aren't sending a CW signal.

Also, the speaker and microphone, if putting a tone oscillator into
the transmitter that way, may add distortion to the tone, which then means
you don't have a CW signal.

If it looks and sounds like CW, then it is CW. But your examples
aren't about sending CW, because you'd be sending peripheral audio along
with the tone.

In other words, it's the results that matter. You can't get those
results with a microphone, and that's why it's not CW.

Michael VE2BVW