Re: QCX - morse decoder question #qcx


Paul Harrison
 

Hi Karlis,

Forget about the Z80 code, the algorithm and accompanying description is important. Use the algorithm to program a decoder, it does not have to be in assemble, modern computer are adequately fast enough to use c, c++, visual basic or whatever take your fancy. Possibly even a sketch with Arduino although I know nothing about that.

Most CW decoders have the problem of spurios characters, missing spaces and adjustment to speed, the algorithm shown makes a very good attempt at avoiding these problems

Paul DJ0CU.


On Thu 8. Nov 2018 at 18:13, Kārlis Goba <karlis.goba@...> wrote:
I used to code in Z80 assembly. However, old code is highly unlikely to be miracle in terms of decoding quality because of resource constraints and the lack of good mathematical methods back then. I haven't yet studied the particular code, but I can bet it's all hard-decision based. And that is not how you even get close to human performance. Most modern methods are machine-learning inspired, so they either model the process and probabilities statistically or use some other soft/fuzzy representation. For high quality some form of language knowledge would have to be incorporated as well, either in form of transition/n-gram probabilities or indirectly as a neural network. That's what largely helps humans - context and the knowledge of what is possible and expected.

--
Karlis YL3JG

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