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AMATEUR RADIO

SimJT is a utility program that generates simulated signals for test
purposes. All of the programs are available free of charge, licensed under New discoveries will
the GNU General Public License. Installation packages for WSJT-X are
available for Windows, Linux and OS X; WSJT and WSPR have Windows have no impact on
and Linux packages, and MAP65 and SimJT are Windows only.
the fundamentals of
For further details about source code and operating systems, visit
the Program Development page. communication

WSJT-X (“Weak Signal Communication, by K1JT”) offers specific
digital protocols optimised for EME (moon bounce), meteor scatter and ore recently, addressing an ITU conference,
ionospheric scatter, at VHF/UHF as well as for LF, MF, and HF propagation. Joe Taylor said: “New discoveries that have
The program can decode fraction-of-a-second signals reflected from Mfundamentally changed or expanded our
ionised meteor trails and steady signals more than 10 dB below the understanding of nature’s laws, or might do so in the
audible threshold. WSJT-X incorporates nearly all popular capabilities of
near future, will not affect the communications world for
programs WSJT and WSPR, while adding comprehensive radio control many decades to come.
and many other features. Check the WSJT-X page and links therein for
details about modes FT8, JT4, JT9, JT65, QRA64, ISCAT, MSK144, and
WSPR. This statement seems like a contradiction to what most
WSJT is the original program, first released in 2001. Version 10 people generally believe. Taylor explained his point of
implements modes JTMS, FSK441, FSK315, ISCAT, JT6M, JT65, and view as follows:
JT4. This is because our fundamental understanding
MAP65 implements a wideband receiver for JT65 signals, optimised of electro-magnetism is already in a mature state.
for EME on the VHF/UHF bands. It can be used together with Linrad (by Maxwell’s equations which have been thoroughly
SM5BSZ) or with direct input from a soundcard or FUNcube dongle. The tested for the past 150 years in principle tell us
program decodes all JT65 signals in a passband up to 90 kHz wide, everything we need to know in order to exploit the
producing a sorted band map of decoded call signs. In a dual polarisation wonders of telecommunications at the speed of light.
system, MAP65 optimally matches the linear polarisation angle of each Our understanding of these laws of nature, including
signal, thereby eliminating problems with Faraday rotation and spatial what they tell us is possible and not possible, is not
polarisation offsets. likely to change. But of course, we can still develop
WSPR (pronounced “whisper”) stands for “Weak Signal Propagation
Reporter.” This program is designed for sending and receiving low power new and improved ways of generating, controlling
transmissions to test propagation paths on the MF and HF bands. Users and detecting electromagnetic radiation, as well as
with internet access can watch results in real time at WSPRnet. Version clever new ways of effectively sharing the spectral
2.11 of WSPR includes FMT, a package of command-line utilities that resources that we have. The fundamental science may
can help you make highly accurate frequency measurements without be mature, but technology’s ability to exploit and
expensive laboratory equipment. The WSPR mode is now included in build upon electromagnetic phenomena is still rapidly
program WSJT-X. developing.”
SimJT generates JT65 and CW test signals with user-specified signal- Limitations of the radio spectrum are a result
to-noise ratio. It is useful for testing the JT65 decoder and the relative of the fundamental laws of nature. Every nation on
capabilities of these two modes. n Earth has, in principle, access to the same spectrum
as everyone else. The amount of accessible oil, on the
other hand, depends on the much more complicated
way the earth formed and evolved over time. These
fuels are not evenly distributed over the earth and
they are expendable. When it’s gone, there’s none left.
The electromagnetic spectrum, on the other hand,
will always be there, whether or not we humans are
around. Moreover, the spectrum can be shared by many
users simultaneously, and shared use can be especially
effective if adequate planning is done in advance.
“Future technologies will surely make even
better uses of wireless communication than we do
today. I foresee plenty of scope for contributions to
new technologies. Information and communication
technologies have much to offer for the betterment of the
human condition everywhere, and perhaps especially so
in the developing world. n
Typical screen of WJST-X communication

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