When I say it is being "held hostage", I don't mean legally or
physically. I mean that just about everyone ... including you, it seems
... thinks that the protocol used in WSJT-X is the only or best way to
do things. Techniques such as LPDC, FEC, and Costas Arrays could be
used to send encoded CW messages (i.e., macros from a logging program)
in digital format that use a different combination of rate, message
length, bandwidth, and number of tones more appropriate for a typical CW
exchange, decode those short message bursts on the receiving end, and
convert them to audible CW for interpretation by the operator. The only
differences apparent to the user would be that the S/N is maybe 8 dB
better and the audible CW (being software generated) is essentially
noise free. I've dug into this enough to know it is possible, but I'm
not proficient enough in either the techniques or software coding to be
able to do it myself. My oldest son is an expert in this stuff (his
career) and has helped me understand the principles, but he has zero
interest in ham radio and doesn't want to bother with it.
Yes, the source code for QSJT-X is open, but it's a large collection of
different routines using different languages ... including legacy
Fortan. I think it would probably be better and more efficient to take
the same techniques and write them from scratch in a common, more modern
language. The science is readily available.
I will say again ... FT8 is merely a rigid implementation of some clever
but standard techniques for signal-to-noise enhancement. FT8 is NOT ...
repeat, NOT ... the definition of how to do it in general. There
wouldn't even be a need to make DSP-enhanced CW channelized ... it could
require tuning around just like RTTY does and it could function in a
bandwidth no wider than 200 Hz ... roughly similar to normal CW ... with
partial capability to function with overlapping signals just like FT8
does now.
I've corresponded with Joe on this a few times. He is simply fully
committed to the various WSJT-X implementations and I understand his
position, but he will readily admit that the same techniques could be
used differently to serve other ham radio forms of operation. My point
is that the FORM of FT8 has become so ingrained in the minds of almost
every ham that nobody with the capability is willing to extend the
precepts of FT8 to other forms of amateur radio communication. The
success of FT8 has effectively constrained the use of what could and
should be advances in the performance of at least CW. The constraint is
perception ... nothing else.
73,
Dave AB7E
On 2/18/2022 11:26 AM, rjairam@gmail.com wrote:
The code for WSJT-X is open source under GPLv3 and absolutely not
proprietary. Joe has written in great detail about the protocol and
the software in QEX and that article is freely available on the WSJT
website.
Nothing is being held hostage. If someone wants to adapt anything from
it, they are more than welcome to.
A lot of what makes FT8 so robust is structured into the protocol
itself - small payloads, use of LDPC and FEC (Low density parity check
and forward error correction) as well as a priori on the decoded side
where cumulative decodes are used to guess the content of partial
decodes. Certainly, repeating CW with different variations in speed
and remembering messages from before and re-creating that is sort of
equivalent but adapting the techniques of FT8 to CW where you have
manual telegraphy probably isn't going to happen.
But if you mean that nobody wants to pick up the source code and do
stuff with it, well maybe that's true. However there have been other
software being developed such as JTDX, MSHV and even WSJT-z which has
used the source code from WSJT-X. Just not for CW because of the
aforementioned challenges in the way FT8 is fundamentally defined.
73
Ria, N2RJ
On Fri, Feb 18, 2022 at 12:59 PM David Gilbert <ab7echo@gmail.com> wrote:
The signal processing techniques utilized in FT8 could have been used to
enhance the signal-to-noise of normal CW in a way that would have been
virtually transparent to the operator. It's truly a shame that WSJT-X
has landlocked those techniques within FT8 in the minds of just about
everyone in our hobby, as well as giving those techniques such a bad
image that nobody seems willing to take up the mantle to fix it.
The signal processing technology behind FT8 is awesome, but it is
neither unique nor proprietary. It should have enhanced the hobby for
all of us, especially for us contesters since almost all of our
transmissions come from keypresses in a logging program anyway. Instead
it is being held hostage to WSJT-X for no real reason other than inertia.
73,
Dave AB7E
On 2/18/2022 8:13 AM, James Cain wrote:
I agree with HA3LN that FT-8 is a terrible blow to what an ARRL director
snidely referred to -- on this reflector -- as "our sandbox." Yes, I play
only unassisted and you call it what you want.
A neighbor guy dropped by and I had just set up my Superstation for this
weekend -- a TS590 on a card table and a 11-foot wire dropped out the 2nd
floor window. "I can talk to Europe, South America, maybe even Japan with
this" said I. "On Morse code."
cain K1TN
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