[Elecraft] Why ESSB and AM?

[Bill Frantz]

I am digging to the bottom of the barrel for reasons to have a 
broad transmit bandwidth.

I don't think the high speed digital mode I'm thinking about has 
yet been invented, but one of the purposes of amateur radio is 
to expriment with new modes. I see such a mode as being useful 
for meteor trail scatter propagation. I think you could send an 
entire exchange segment (called station, signal report, and 
transmitting station) in under 10 milliseconds. That speed would 
allow several QSOs during the 1-3 second lifespan of the ionization.

With forward error correction in the protocol, the software 
could calculate the signal report based on the number of wrong 
bits received and the signal strength, the 5 and the 9 of a 
conventional SSB report.

With the mode filling the whole bandwidth ala PSK31 filling the 
31 Hz bandwidth, I don't think the 80 dB noise pedestal is a 
significant factor. But I certainly could be wrong. (It wouldn't 
be the first time.)

As a rag chewer at heart, that kind of QSO isn't quite my cup of 
tea, but it might appeal to the people who enjoy WSJT moon 
bounce. Amateur radio is a very big tent.

Cheers - Bill, AE6JV

On 9/23/12 at 7:47, lists at subich.com (Joe Subich, W4TV) wrote:

>>ESSB might be useful to transmit a wide-band, high bit rate
>>digital mode via a computer sound card. Those sound cards have
>>at least 15KHz bandwidth,
>
>ESSB is limited to 4.0 KHz but is not available in digital modes
>(DATA A or AFSK A).  While ESSB might be useful for those modes in
>which "panoramic" (click in a 2.5 to 3 KHz wide waterfall) operation
>is the norm, nearly every transmitter has an "in band" noise pedestal
>(broadband noise) the width of the transmit filter that is only 60
>to 80 dB below the transmitter's PEP output.

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