[TenTec] cw creation

[Bob Stephens]

Steve,

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)

tnx & 73, Bob KB1CIW

At 08:07 PM 4/24/2005 -0400, you wrote:

>The DSP stage in many modern rigs actully contains the entire radio. The
>rest of the rig converts the DSP's output to the right frequency. SSB, FSK,
>CW, AGC, Detection is all done inside the DSP stage. The input and output
>frequency of this DSP stage varies. The Jupiter/Pegasus DSP uses 11 khz for
>I/O. This means that the other conversion stages in the rig must convert the
>ham bands down to 11 khz for reception and back up for transmission. When
>you tap the cw key, you are actually causing the DSP to run a process that
>results in the DSP stage outputing an 11 khz carrier. This carrier is then
>converted to the ham bands and amplified. This is a far cry from "feeding
>audio into a mic. jack"!

><snip>

>Am I making sense?
>Steve Ellington
>N4LQ at iglou.com
>----- Original Message -----
>From: "Bob Stephens" <bstephens1 at mindspring.com>
>To: "Discussion of Ten-Tec Equipment" <tentec at contesting.com>
>Sent: Sunday, April 24, 2005 7:31 PM
>Subject: Re: [TenTec] cw creation
>
>,snip>
>
>... an article about High Speed CW for Meteor scatter work called
> >>"Utilizing the Constant Bombardment of Cosmic Debris for Routine
> >>Communication" by Shelby Enis, W8WN He explains how "cw" is produced as
> >>used in one type of meteor scatter work and he writes:
> >
> > "Keying is done by an injected audio tone [using sound card technique] (as
> > is done with many of the digital modes), ...<snip>. The emission type is
> > designated J2A. This method produces keying that is indistinguishable from
> > on/off keying of the main carrier, and is the *same method* [my emphasis]
> > used by many rigs to produce CW."
> >
> > So, let's see if I understand this correctly . In many modern rigs keying
> > is done by audio type keying that results in J2A rather than true A1A
> > emission. On the receiver end we can't tell the difference. This was first
> > done unsuccessfully in the Collins. In modern rigs today this is often
> > successfully done using  DSP. Is this basically true?
> >
> > Questions:
> > 1.Can I assume that the Orion, Jup/Peg and perhaps the 756/746 are all
> > producing J2A?
> >
> > 2. Can non DSP rigs be used to transmit legal J2A if sound card technology
> > is used ?
> >
> > 3. Were there other rigs (besides Collins) that used audio type keying
> > without DSP? Is DSP the only way to produce clean legal J2A ?
> >
> > 4. Can I assume that the classic TT rigs produce A1A and not J2A?
> >
> > 5. I still don't really understand what J2A audio type keying is. What is
> > the difference between J2A and simply keying the rig in SSB mode while
> > holding the microphone to the output of a code practice oscillator?
> >
> > It is possible that I'm totally clueless <grin> ... and so I ask questions
> > ;-)
> >
> > tnx & 73
> > Bob, KB1CIW
> >
> >
> >
> >
> > --
> > No virus found in this outgoing message.
> > Checked by AVG Anti-Virus.
> > Version: 7.0.308 / Virus Database: 266.10.2 - Release Date: 4/21/2005
> >
> >
> > _______________________________________________
> > TenTec mailing list
> > TenTec at contesting.com
> > http://lists.contesting.com/mailman/listinfo/tentec
> >
>
>_______________________________________________
>TenTec mailing list
>TenTec at contesting.com
>http://lists.contesting.com/mailman/listinfo/tentec
>
>
>
>--
>No virus found in this incoming message.
>Checked by AVG Anti-Virus.
>Version: 7.0.308 / Virus Database: 266.10.2 - Release Date: 4/21/2005


-- 
No virus found in this outgoing message.
Checked by AVG Anti-Virus.
Version: 7.0.308 / Virus Database: 266.10.2 - Release Date: 4/21/2005