> You write, "When you tap the cw key, you are actually causing
> The DSP to run a process that results in the DSP stage
> outputing an 11khz carrier"
>
> That does not sound like "injecting a tone". What you
> describe sounds like A1A emission - turning a carrier on and
> off . Obviously, this is at a lower frequency than the
> classic method, but it still sounds like the carrier is being
> keyed on and off thus it appears to be A1A rather than J2A .
>
> Was Shelby Enis, W8WN wrong when he wrote "Keying is done by
> an injected audio tone...The emission type is designated J2A
> ... and is the same method used by many rigs to produce cw "?
> Or perhaps I am misunderstanding him ? (his full quote is at
> the bottom)
I think we're getting our tongues wrapped around the ideas crosswise here.
As Steve said, some Collins radios (at least the KWM-2 and I think the
32S-1) used the audio tone injection method. And it wasn't a particularly
happy marriage [particularly in the KWM-2).
A keyed carrier (a lot of assumptions and hand waving) results in a single
frequency being transmitted. A tone modulated SSB transmitter (more
assumptions and hand waving) has a carrier (reduced) and an opposite
sideband (also reduced). So it results in THREE transmitted signals -- the
one you want, and two more you don't want at some (hopefully) reduced level.
If the opposite sideband and carrier are reduced far enough, it looks like
A1 -- if they aren't you might at least hear from an OO if the FCC :-)
The DSP stage outputing an 11 Khz carrier is NOT the same thing as a "tone".
It is a real, single frequency, RF carrier that gets mixed in several
heterodyne stages to the desired output frequency. And is standard,
ordinary, everyday A1.
I haven't dug into it, but I believe the Orion (and any other current DSP
radio worth its salt) will do the latter -- true A1.
Grant/NQ5T
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