Good afternoon Joe K1JT,
Nice outreach to the WSJT-X community.
I don’t consider myself a WSJT-X user.
I’m 99% CW.
However, your program is super-fascinating.
With guidance from you, I’ve been able to write MATLAB code which takes a
user message such as “CQ VA2GJ FN35” and generates a wave file which is
readable by FT8. This MATLAB code is not a translation of the WSJT-X code
but rather a coding of concepts.
In the process I’m getting a better understanding of call sign formats,
grid square formats, hashing, cyclic redundancy code, shift-registers,
parity word generation, Costas array, symbol packing, symbols to
continuous-phase FSK and Gaussian-shaped pulses.
The outline of the processing:
Read the user message
Parse the user message
Process the call sign
Process the grid square
Pack the 77-bit source-encoded message
Calculate the cyclic redundancy check from the source-encoded message using
shift-registers
Calculate the 83-bit parity
Pack and gray-code
Organize channel symbols
Convert channel symbols into continuous-phase 8-bit frequency-shift-keyed
tones
Smooth with Gaussian-shaped pulses
Use the raised cosine for smoothing the onset and release transients
Save as a wav file
All the best,
73 de VA2GJ
Gérald
On Tue, Apr 26, 2022 at 2:09 AM Charles Suckling via wsjt-devel <
wsjt-devel@lists.sourceforge.net> wrote:
> Hi Joe
>
> Building here on Windows, 64 bit only. Needed some help from Uwe to get
> it running again. Using the JTSDK toolset, inside a VM on Windows 10. I
> have not been able to build debug versions with it. Uwe hasn't been able
> to help with that. Not sure if its a deficiency my end, or in the toolset.
>
> Programming skills are very limited. I dabbled with Fortran (4?) at
> University. Tend to look for examples in the code which do what I want,
> especially in C++, and needed help from Bill on a number of occasions.
>
> With Bill's help I was able to stage and commit with Git, and made some
> notes at the time, but not confident I could do it again.
>
> Yes, I have made a number of changes to the code over time. Fixing TX
> freq to 1000Hz in QRA64 was one of the first, as Rex and I used to forget
> it changed to 1500 in Echo mode and often someone would forget when going
> to QRA64. I also enabled Autosequencing to QRA64, mainly to help Rex as
> his workload in his expeditions was very high. I also found it very
> convenient. May also have added single tone messages around the same
> time. Later, added OnDxEcho and Call DX Doppler methods, mainly for the
> 1296 folks who tend to use them traditionally, although CFOM is becoming
> increasingly used now (good!). Got familiar with User Guide and have made
> some contributions to that. I think I can still do that. Also, made some
> changes to the simulators to add single tone capability, and file numbering
> to be compatible with averaging (with a little help again from Bill). Also
> added moon distance to Astro.
>
> I would not go so far as to say there is much of the code that I (fully)
> understand. Latterly, Bob pointed to the feature in Notepad ++ that allows
> you to search the entire repository for a variable name, or other phrase,
> which has helped to figure out what is 'connected' to what. Passing
> variables from one subroutine to another is beyond me, other than via files
> (as we did with the recent work on Echo mode).
>
> Btw, thanks for adding Clear Average to Echo per Bob's request. That will
> be indeed useful.
>
> Charlie
>
>
>
> On Mon, 25 Apr 2022 at 18:02, Joe Taylor via wsjt-devel <
> wsjt-devel@lists.sourceforge.net> wrote:
>
>> When I started work on WSJT some 21 years ago, my principal goal was to
>> help bring amateur weak-signal communication techniques into the
>> twenty-first century -- and in doing so, to help spread knowledge of
>> modern communication theory into the amateur radio community.
>>
>> By 2005 WSJT was well established but mostly used for special purposes
>> like meteor scatter and EME ("moonbounce"). A stable development path
>> had been established: the program was fully Open Source, licensed under
>> the GNU General Public License, and it could be built by anyone from
>> source code using freely available compilers and development tools. At
>> this time WSJT was coded in a combination of Python, Fortran, and C. A
>> re-write in 2012 created the present program, WSJT-X, using the Qt
>> platform and C++ language in addition to Fortran and C.
>>
>> To help gauge the extent to which my original educational goals are
>> being met, we in the core development team are interested to know how
>> many WSJT-X users are currently building the program for themselves,
>> from source code. If you are doing so, we would appreciate an email
>> response -- either publicly, to this list, or in a private email to me.
>> All responses will be appreciated, but particular things you might want
>> to mention in your message include these:
>>
>> - Building on what platform? Windows, Linux, macOS, or other?
>>
>> - What are your particular programming skills and interests?
>>
>> - Are you making changes to the code? If so, toward what end?
>>
>> - What portions of the code have you studied well enough to understand?
>>
>> Many thanks -- I look forward to hearing from you!
>>
>> -- 73, Joe, K1JT
>>
>>
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>> wsjt-devel@lists.sourceforge.net
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