[Elecraft] FT8: "Magic radio"?

[Neil Zampella]

Wes,

you're taking that out of context.   The structured messages allow for 
redundancy if some of the original message is missing. The decoder can 
take the sync symbols so that the system can understand what type of 
message it is, it still needs the callsign and signal report.

More details can be found here: 
https://physics.princeton.edu/pulsar/k1jt/wsjtx-doc/wsjtx-main-1.9.1.html#PROTOCOLS
and here 
https://physics.princeton.edu/pulsar/k1jt/FrankeTaylor_QEX_2016.pdf 
which covers JT65, but which forms some of the basis for the other JT/FT 
protocols.

Neil, KN3ILZ


On 7/3/2018 5:16 PM, Wes Stewart wrote:
> In a message to this group back in February I wrote:
>
>    Quoting G4WJS: "For FT8 the net effect is that
>    up to about 5 seconds of a message may be missing yet still
>    be decoded. The amount missing can be either a truncation or
>    parts of the message below the decoding threshold. The FT8
>    message is structured with sync symbols at the start, middle
>    and end so missing the start or end may have less impact
>    than missing other parts since mostly sync symbols may be
>    lost and they contain no message information."
>
> Hence, I dubbed the mode, "Imaginary"  since it hears things that 
> aren't there.
>
> Wes  N7WS
>
> On 7/3/2018 12:36 PM, Wayne Burdick wrote:
>> Overheard yesterday on 40 meter SSB, in reference to FT8:  “Given the 
>> level of automation and whatnot, maybe they should call it ‘magic 
>> radio’ instead of ‘ham radio’.”
>>
>> New contest category?
>>
>> Wayne
>> N6KR
>>
>>
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