Now as the first preliminary information has been published, I would
like to give you some first-hand information on this topic:
We have been working intensively for several weeks/months on a
so-called FT8 SuperFox (sub-)mode for WSJT-X. This SuperFox mode is
technically far superior to the previous Fox/Hound protocol. And
I'll be honest, this is also our answer to the many "fake" Fox
stations that have been around recently.
Here are the key points:
- The SuperFox station can transmit up to 9 messages
simultaneously without reducing the dB values received by the
Hounds. This means a system gain of approx. +10 dB compared to
the conventional Fox/Hound (or MSHV multi-stream) operation with
5 slots !! This is possible by transmitting a special single constant envelope, using a 1.5
KHz-wide waveform.
- The
Hound stations will transmit normal FT8 signals as
before, but can call on all frequencies when in
SuperFox mode, i.e. also below 1000 Hz and up to 5000 Hz
(provided the receiver of the SuperFox station supports this).
- There is a new verification system. A genuine SuperFox station
can identify itself with a digital signature. The user
recognizes this by an additional message such as "DG2YCB
verified". And in parallel, the normally red "Super Fox" label
switches to green.
- A SuperFox station can optionally send free text messages up
to 26 characters long, for example to announce QSY or something
similar.
- To make the daily use easier I programmed the following
convenience feature: Right-click on the FT8 button to toggle
SuperFox mode On/Off. This means that you will be able to switch
to Hound mode via the "H" button like before. All you then have
to do is to right-click on the FT8 button when a SuperFox
station appears on the bands. Another right-click on the FT8
button will bring you back to the standard Hound mode. Pretty
simple and intuitive!
- The right-click on the FT8 button also works when in Fox mode,
by the way. This will allow SuperFox operators to quickly switch
between Fox and SuperFox mode.
Important: Every Hound station will have to use at least the
upcoming WSJT-X 2.7.0-rc5 version (or my 2.7.1-devel "improved"
variant of it) to be able to receive SuperFox messages !!
How far are we and what's next?
The new SuperFox mode is already fully functional. But of course
there are still a number of technical details to clarify and solve.
Keep in mind that the technology under the hood is quite complex and
brand new. That's why there will be a few more internal tests first.
The SuperFox mode will then be rolled out in time for the N5J Jarvis Island DXpedition.
So far nor now. Stay tuned!
73 de DG2YCB,
Uwe
(WSJTx - Improved)