Update the README file -- which hasn't been touched in years!

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Joe Taylor 2019-07-22 11:35:26 -04:00
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README
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Copyright (C) 2001 - 2018 by Joe Taylor, K1JT. Copyright (C) 2001 - 2019 by Joe Taylor, K1JT.
WSJT-X is a computer program designed to facilitate basic amateur WSJT-X Version 2.1 offers ten different protocols or modes: FT4, FT8,
radio communication using very weak signals. The first four letters in JT4, JT9, JT65, QRA64, ISCAT, MSK144, WSPR, and Echo. The first six
the program name stand for “Weak Signal communication by K1JT,” while are designed for making reliable QSOs under weak-signal
the suffix “-X” indicates that WSJT-X started as an extended (and conditions. They use nearly identical message structure and source
experimental) branch of the program WSJT. encoding. JT65 and QRA64 were designed for EME (“moonbounce”) on the
VHF/UHF bands and have also proven very effective for worldwide QRP
communication on the HF bands. QRA64 has a number of advantages over
JT65, including better performance on the very weakest signals. We
imagine that over time it may replace JT65 for EME use. JT9 was
originally designed for the LF, MF, and lower HF bands. Its submode
JT9A is 2 dB more sensitive than JT65 while using less than 10% of the
bandwidth. JT4 offers a wide variety of tone spacings and has proven
highly effective for EME on microwave bands up to 24 GHz. These four
“slow” modes use one-minute timed sequences of alternating
transmission and reception, so a minimal QSO takes four to six minutes
— two or three transmissions by each station, one sending in odd UTC
minutes and the other even. FT8 is operationally similar but four
times faster (15-second T/R sequences) and less sensitive by a few
dB. FT4 is faster still (7.5 s T/R sequences) and especially well
suited for radio contesting. On the HF bands, world-wide QSOs are
possible with any of these modes using power levels of a few watts (or
even milliwatts) and compromise antennas. QSOs are possible at signal
levels 10 to 15 dB below those required for CW.
WSJT-X Version 1.6 offers five protocols or “modes”: JT4, JT9, JT65 Note that even though their T/R sequences are short, FT4 and FT8 are
WSPR, and Echo. The first three are designed for making reliable QSOs classified as slow modes because their message frames are sent only
under extreme weak-signal conditions. They use nearly identical once per transmission. All fast modes in WSJT-X send their message
message structure and source encoding. JT65 was designed for EME frames repeatedly, as many times as will fit into the Tx sequence
(“moonbounce”) on the VHF/UHF bands and has also proven very effective length.
for worldwide QRP communication on the HF bands. JT9 is optimized for
the LF, MF, and lower HF bands. It is 2 dB more sensitive than JT65
while using less than 10% of the bandwidth. JT4 offers a wide variety
of tone spacings and has proved very effective for EME on microwave
bands up to 24 GHz. All three of these modes use one-minute timed
sequences of alternating transmission and reception, so a minimal QSO
takes four to six minutes — two or three transmissions by each
station, one sending in odd UTC minutes and the other even. On the HF
bands, world-wide QSOs are possible using power levels of a few watts
and compromise antennas. On VHF bands and higher, QSOs are possible
(by EME and other propagation types) at signal levels 10 to 15 dB
below those required for CW.
WSPR (pronounced “whisper”) stands for Weak Signal Propagation ISCAT, MSK144, and optionally submodes JT9E-H are “fast” protocols
Reporter. The WSPR protocol was designed for probing potential designed to take advantage of brief signal enhancements from ionized
propagation paths using low-power transmissions. WSPR messages meteor trails, aircraft scatter, and other types of scatter
normally carry the transmitting stations callsign, grid locator, and propagation. These modes use timed sequences of 5, 10, 15, or 30 s
transmitter power in dBm, and they can be decoded at signal-to-noise duration. User messages are transmitted repeatedly at high rate (up to
ratios as low as -28 dB in a 2500 Hz bandwidth. WSPR users with 250 characters per second, for MSK144) to make good use of the
internet access can automatically upload their reception reports to a shortest meteor-trail reflections or “pings”. ISCAT uses free-form
central database called {wsprnet} that provides a mapping facility, messages up to 28 characters long, while MSK144 uses the same
structured messages as the slow modes and optionally an abbreviated
format with hashed callsigns.
WSPR (pronounced “whisper”) stands for Weak Signal Propagation
Reporter. The WSPR protocol was designed for probing potential
propagation paths using low-power transmissions. WSPR messages
normally carry the transmitting stations callsign, grid locator, and
transmitter power in dBm, and they can be decoded at signal-to-noise
ratios as low as -31 dB in a 2500 Hz bandwidth. WSPR users with
internet access can automatically upload reception reports to a
central database called WSPRnet that provides a mapping facility,
archival storage, and many other features. archival storage, and many other features.
Echo mode allows you to detect and measure your own lunar echoes, even Echo mode allows you to detect and measure your own stations echoes
if they are far below the audible threshold. from the moon, even if they are far below the audible threshold.
WSJT-X provides spectral displays for passbands up to 5 kHz, flexible WSJT-X provides spectral displays for receiver passbands as wide as 5
rig control for nearly all modern radios used by amateurs, and a wide kHz, flexible rig control for nearly all modern radios used by
variety of special aids such as automatic Doppler tracking for EME amateurs, and a wide variety of special aids such as automatic Doppler
QSOs and Echo testing. The program runs equally well on Windows, tracking for EME QSOs and Echo testing. The program runs equally well
Macintosh, and Linux systems, and installation packages are available on Windows, Macintosh, and Linux systems, and installation packages
for all three platforms. are available for all three platforms.
WSJT-X is an open-source project released under the GPLv3 license (See WSJT-X is an open-source project released under the GPLv3 license (See
COPYING). If you have programming or documentation skills or would COPYING). If you have programming or documentation skills or would
like to contribute to the project in other ways, please make your like to contribute to the project in other ways, please make your
interests known to the development team. The projects source-code interests known to the development team. The projects source-code
repository can be found at https://sourceforge.net/projects/wsjt, and repository can be found at https://sourceforge.net/projects/wsjt, and
most communication among the developers takes place on the email communication among the developers takes place on the email reflector
reflector https://sourceforge.net/p/wsjt/mailman. User-level https://sourceforge.net/p/wsjt/mailman. User-level questions and
questions and answers, and general communication among users is found answers, and general communication among users is found on the
on the https://groups.yahoo.com/neo/groups/wsjtgroup/info email https://groups.yahoo.com/neo/groups/wsjtgroup/info email reflector.
reflector.
Project web site: Project web site:
http://www.physics.princeton.edu/pulsar/K1JT/wsjtx.html https://www.physics.princeton.edu/pulsar/K1JT/wsjtx.html
Project mailing list (shared with other applications from the same Project mailing list (shared with other applications from the same
team): team):
https://groups.yahoo.com/neo/groups/wsjtgroup https://groups.yahoo.com/neo/groups/wsjtgroup