Changes in WSJT 5.9.3: January 26, 2006 --------------------------------------- This is a minor maintenance release. 1. New Help screen provides a list of available suffixes and add-on DXCC prefixes. 2. The occasional error message about "images do not match" has been trapped and should no longer occur. 3. Code that required one's own grid locator to be entered with first two letters in upper case, last two in lower case, has been made case insensitive (as it should have been). 4. Initialization of the PTT line to the "OFF" state has been fixed. Changes in WSJT 5.9.2: January 16, 2006 --------------------------------------- Enhancements ------------ 1. Thread priorities have been adjusted for smoother operation. 2. The JT65 decoder has been given improved immunity to garbage data (birdies, QRM, etc). It exhibits better performance on strong signals and provides more accurate estimates of their S/N. 3. The FSK441 decoder produces less on-screen gibberish when processing mouse-picked decodes. 4. The JT6M decoder now makes better use of Freeze and Tol. You can set the value of "Freeze DF" by using the Right/Left arrow keys. (This feature is also useful in JT65 mode.) 5. On-screen font sizes can be set by using Windows Notepad to edit the file wsjtrc.win. If your screen has resolution greater than 1024 x 768, or if you have old eyes like mine, you may want to increase the font sizes from 8 and 9 points (first three lines of the file) to, say, 9 and 10 points. 6. A simulator mode is now built into WSJT for testing purposes. It is presently most useful in JT65 mode. By entering, say, "#-22" in the text box for Tx6, you signify that the program should generate its Tx audio files with the signal embedded in white gaussian noise, 22 dB below the noise power in a 2.5 kHz bandwidth. You can direct this signal into a second computer running WSJT, for example to test the decoder or to practice operating in JT65 mode. You can even have the two computers "work each other" in a simulated QSO, although changing messages of course requires operator action. 7. Dividing lines are now provided on the waterfall display between spectra corresponding to wave files read from disk. 8. The PTT line is explicitly set low on program startup. 9. The F10 key brings up the SpecJT screen (if it was hidden) and toggles foreground and focus status between the WSJT and SpecJT screens. 10. You can use the Alt-F and Alt-Z keyboard shortcuts to toggle "Freeze" and "Zap" on and off. 11. "Accelerated decoding" has been removed from the Setup menu. In effect, this option is now always ON. 12. Text windows are now cleared when switching between modes. 13. Linux and FreeBSD versions (see below) offer PTT control via parallel port, as well as serial port. They offer sound support via ALSA and OSS. Bug Fixes: ---------- 1. The use of non-threadsafe code for FFTs could cause occasional and unpredictable program crashes. Fixed. 2. A bug in the JT65 decoder could (rarely) cause large errors in the reported level of strong signals. Fixed. 3. The program could be made to crash by trying to read a very short wave file. Fixed. 4. "Save None" now works as it should. Please note: ------------ When entering your grid locator on the Setup->Options page, use upper case for the first two letters and lower case for the last two. For example, for K1JT the locator is FN20qi. For Curious Users, and Especially for Programmers ------------------------------------------------- WSJT is no longer a one-person effort, and the program no longer runs only under Microsoft Windows. WSJT is now a full-fledged Open Source project, with an active working group making contributions to future development. Source code is now stored in a public repository under control of a version control system called "Subversion," or SVN. You can learn more at http://developer.berlios.de/projects/wsjt/. The first significant result of the group effort has been to create versions of WSJT that run under the Linux and FreeBSD operating systems. Porting WSJT to the Macintosh platform should be straightforward, but has not yet been done. If you are interested in testing and using WSJT on your own Linux or FreeBSD system, we'd like to hear from you. Please note that the present Linux and FreeBSD versions are intended mainly for programmers. You need to know your way around these operating systems to be able to install them. If you feel that you can usefully contribute to the future development of WSJT on any platform, we would also like to hear from you! We could use help with documentation and website maintenance, as well as actual programming. The present WSJT working group consists of: Diane Bruce, VA3DB James Courtier-Dutton Bob McGwier, N4HY Jonathan Naylor, ON/G4KLX Stewart Nelson, KK7KA Joe Taylor, K1JT Kaj Wiik, OH6EH Changes in WSJT 5.9.0: November 16, 2005 ------------------------------------------ 1. JT65 decoding has been made faster and significantly improved in other ways. Three new options appear on the Decode->JT65 menu: "Fast", "Normal", and "Exhaustive". The program is most sensitive if you choose "Exhaustive". Choosing "Normal" will make decoding slightly less sensitive, but the loss is not great, and decoding can be twice as fast. The "Fast" setting is faster still, but can be less sensitive by 2 dB or more in some cases. If you have a 1.5 GHz or faster computer, use "Exhaustive". With a slower computer you may want to experiment with the other settings. 2. In JT65 mode, double-clicking on the waterfall (SpecJT window) or on the red curve (main window) sets "Freeze DF" to the selected frequency, turns Freeze ON, sets Tol to 50 Hz, and invokes the decoder. Using this feature, you can quickly decode a transmission at several different values of DF. I find this feature to be *extremely* useful. 3. The range of DT values searched to establish synchronization has been doubled, now extending from -2 to +10 seconds. The reported values of DT are more accurate, as well. You should normally expect EME signals to have DT in the range 2 to 3 seconds, but the program will now synchronize properly even if DT is well outside this range. 4. WSJT now offers the ability to correct for errors in soundcard input and output sampling rates. Numbers displayed in the first panel of the status bar (at lower left of the main screen) give the ratio of actual sample rates for input and output to the correct value, 11025 Hz. The numbers should stabilize within about one minute after program startup. If they fall in a "safe" range between about 0.9990 and 1.0010, you have a good sound card (at least in respect to sampling frequency). You can then leave the entry fields "Rate In" and "Rate Out" on the "Setup -> Options" page at their default values, 1.0. If your soundcard gives one or both numbers well outside the safe range, you should enter the displayed errant numbers as "Rate In" and/or "Rate Out" on the Setup->Options page. This needs to be done only once; subsequent changes in the last decimal place of the displayed values are not very significant, and can be safely ignored. The result of this procedure is that your Tx signal will be "trimmed" so that your tone spacings in time and frequency are more nearly correct. In addition, your digitized Rx signals will be adjusted so that the software can properly interpret them. This trimming is an important procedure. Some recent sound cards produce sampling error factors as low as 0.9932 or as high as 1.0068. If uncorrected, such results can degrade your S/N in WSJT modes by 2 dB or more. If one of the measured sample rates differs from the corresponding value specified for "Rate In" or "Rate Out" by more than 0.1%, a red warning label will appear just below the graphical area on the main screen. 5. The graphical display of information obtained during JT65 decoding has been enhanced. As before, a red line illustrates the maximum correlation between the pseudo-random sync tone pattern and the received signal at each value of frequency offset, DF. A blue line shows the correlation at the best DF, plotted as a function of time offset, DT. If a shorthand message is detected, two new lines colored magenta and orange replace the red and blue lines. The new lines illustrate phase-resolved spectra measured in each of the two phases of the shorthand square-wave pattern. A properly detected shorthand message will show a peak in the magenta curve, followed at a specified distance by a peak in the orange curve. The correct locations of the two peaks are marked by small yellow ticks. Unlike the alternating shorthand message tones, birdies will appear with approximately equal amplitudes in the magenta and orange curves. 6. For the convenience of temporary DXpeditions, a new JT65 feature permits use of add-on DXCC prefixes that are not in the published list of supported prefixes. Both stations in a QSO must enter the required prefix (for example, PJ8 or FS) in a box on the Setup->Options page. The effect will be to temporarily add the entry to the table of supported prefixes. 7. The Setup->Options page has new entry fields labeled "Source RA" and "Source DEC". You can enter the current right ascension and declination of a radio source to be used for system calibration, or perhaps a pulsar or a deep space probe that you wish to detect. The program will display (on the Astronomical Data screen) the current Azimuth and Elevation of the specified object at your station. The source Azimuth and Elevation are also written every second to the file azel.dat, in case you have automated tracking capabilities that depend on this information. 8. For contest-style operations, the Setup->Options menu has an item labeled "F4 sets Tx6". If this item is checked, when you hit F4 to clear the To Radio box the program will turn Freeze OFF and set the Tx message number to 6. 9. To facilitate the coming release of the full source code of WSJT under the GNU General Public License, the proprietary soft-decision Reed Solomon decoder has been removed from WSJT proper and made into a separate executable module, KVASD.EXE. This change is transparent to the user, and the full benefit of the soft-decision decoder is still available. An open source hard-decision decoder is also provided; it's what you get when you select the "Fast" JT65 decoding option. 10. In WSJT 5.8.6, if the value of "Freeze DF" (as displayed in the Status Bar) differs from the sync tone frequency by more than "Tol", shorthand decoding was suppressed even if Freeze was not checked. This is a bug, and it has been fixed. 11. Earlier versions of WSJT had a bug that could cause the "Zap" function to notch out a valid sync tone. Fixed. 12. The Help screens called up by F1 and Shift-F1 have been updated. Be sure to read these screens: they contain many operational conveniences that you may not have discovered! 13. At scrolling speed 5, the time labels and "minute separator" lines were displayed erratically and the CPU load was excessive. Fixed. 14. Signal strength measurements above -20 dB were formerly compressed and significantly underestimated. This has been fixed. 15. Decodings of the average of many properly synchronized transmissions would sometimes go from "good" to "bad" after approximately 8-12 transmissions. This was a bug, and it has been fixed. 16. Several bugs in the FSK441 decoder have been fixed. Both automatic decoding and mouse-picked decoding have been improved. 17. Changing WSJT modes now sets Auto to OFF, Tol to 400, and the Tx message number to 1. 18. The generated audio for CW ID in FSK441 and JT6M modes has been moved to 440 Hz, to avoid possible confusion with the other tones used in these modes. 19. Readout of "Rx noise" on the main screen is now highlighted in red if the level is outside the range -10 to +10 dB. 20. The Monitor button is no longer highlighted in green while you are transmitting. 21. No attempt is made to decode if the Rx level is very low -- for example, if your receiver is turned off. 22. If the Grid box does not contain a valid locator, readouts of azimuth and distance are suppressed. 23. Keying of the audio tone to produce Morse code has been softened to suppress key clicks. 24. Transmitted messages recorded in the file ALL.TXT are now identified as to mode, and shorthand transmissions are noted as such. 25. A number of other very minor bugs have been fixed. Changes in WSJT 5.8.6 --------------------- 1. Audio input and output has been modified in a way that accommodates certain soundcards (e.g., SB Live!) that did not work correctly with WSJT 5.8.3. 2. New item on Setup->Options menu to select whether GenStdMsgs forces Tx message number to 1. 3. Status of all selectable items on Setup->Options menu is preserved on program restart. 4. If a CQ is transmitted in JT65 mode, the Sked box is automatically unckecked. 5. In v5.8.3, entering the same callsign and locator information in MyCall and ToRadio/Grid could cause the program to freeze. Fixed. 6. If MyCall includes an extra prefix, as in 4X/ZL1RS, the standard JT65 messages should not include a grid locator. Fixed. 7. The "ms" parameter has been removed from the Soundcard status readout at bottom left. Separate sample-rate factors are now displayed for audio input and output, but only if "Enable diagnostics" is checked on the Setup menu. 8. The SpecJT screen may now be made invisible by clicking on "X" in the upper right corner. To restore it to visible status, click on View->SpecJT on the main screen. 9. Decoded text lines in JT6M mode were sometimes too long, causing end-of-line wrap-around. Fixed. 10. Some diagnostic messages printed to console window have been removed. 11. The values of S, Sync, Clip, Zap and NB are now preserved when the program is terminated and restarted. 12. Version 5.8.3 was unable to read back its own recorded wave files. Fixed. 13. A programming error in the JT65 shorthand message decoder has been fixed. Under certain conditions, this error could cause false decodes of shorthand messages. 14. The logic of file saving commands Save Last, Save decoded, etc., has been corrected. 15. Wave files read from disk will now produce spectral plots on the waterfall display if Monitor is OFF. 16. The CW ID feature has been implemented. 17. The mapping of signal levels to pixel colors and its dependence on settings of Brightness and Contrast controls has been changed so as to improve sensitivity to very weak signals. 18. In v5.8.3, changing Dsec would create erroneous results for the displayed soundcard sample rate factor. Fixed. 19. Running in JT65 mode with Dsec>0 caused transmission errors (including a gap in transmitted tones at t = 38-41 s), and the resulting transmission was unreadable. Fixed. 20. Undesired resizing of main screen could occur when a long FSK441 message was transmitted. Fixed. 21. The "yellow line" displayed in the graphical area in JT6M mode was computed incorrectly in version 5.8.3. Fixed. 22. When running at speeds 1-5, the waterfall spectrum may optionally be "flattened" to remove rolloff at edges. To enable this feature, check "Flatten spectra" on the SpecJT Options menu. COMMENTS ON SOUND CARDS ----------------------- In general, "high end" sound cards offer no advantages when used with WSJT. Motherboard AC-97 compliant sound systems are cheap and work well. If you do need to buy a sound card for use with WSJT, my advice is to get a simple one. You do NOT need 8-channel surround-sound, wavetable synthesis, special effects, etc. Those features are for games and listening to music, and they will be wasted on WSJT. Likewise, you do not need 24-bit A/D and D/A conversions. Specifications having to do with signal/noise ratio are quite irrelevant to use with WSJT, as you should never be operating in a regime where A/D quantizing noise (or any other noise generated in the sound card) contributes significantly to the system S/N. If you have a choice, get a card that offers a *native* sampling rate of 44100 or 11025 Hz, or both. (Unfortunately, it is often very difficult to tell from the manufacturer's literature whether this capability is present or not.) If native sampling at 11025 Hz is available -- or if the manufacturer has at least provided a well-designed resampling capability -- the soundcard sample-rate factors (displayed by WSJT in the bottom left corner, if "Setup->Enable diagnostics" is checked) should both be very close to 1.0000. Changes in WSJT 5.8.3 --------------------- 1. The Dsec parameter was not working properly in v5.8.1. Fixed. 2. CPU load at high waterfall speeds has been substantially reduced. 3. Saving cumulative file of decoded text is no longer optional. The file name has been changed to ALL.TXT, to reflect use of this file for transmitted as well as decoded text. 4. Logic for green bar illustrating region searched for sync tones has been corrected. 5. Bug producing index error in "plot_yellow" is fixed. 6. Bug causing crash in CW mode if TRPeriod > 60 s is fixed. 7. Tabular listing of Audio devices has been clarified. 8. Name at top of waterfall screen has been changed to "SpecJT" so that its icon can be distinguished from that of main screen. 9. VOX control of T/R sequencing is now permitted by setting the COM port to 0. 10. Exit from program with the "To Radio" box empty caused error message and substitution of default parameters on restart. Fixed. 11. Default FSK441 message #5 for EU has been changed to "73 MyCall" (which I am told conforms with standard EU practice). 12. Lower case letters are now acceptable in entries on Setup->Options screen, and will be translated appropriately to upper case in transmitted messages. 13. The file AZEL.DAT has been moved to the WSJT6 installation directory. 14. The "Sh Msg" box was always checked when entering FSK441 mode. It now remembers its state if you had unchecked it. 15. Keyboard shortcuts have been implemented for most on-screen controls. Use F1 to see a full listing. 16. "Gen Std Msgs" now sets the Tx message to #1 in all WSJT modes. 17. Self-echo doppler value has been replaced by "Dgrd" in the astronomical data displayed on the main screen. 18. The audio stream has been trimmed by 0.5 s at the start of FSK441 and JT6M Rx sequences, to prevent possibly copying one's own Tx signal. (Is this enough?) 19. Two header parameters in wave files recorded by WSJT have been corrected so that the files can be read correctly by Windows Sound Recorder. 20. Four-digit grid locators no longer produce incorrect azimuth headings. 21. Logic error in the waterfall's horizontal scrolling mode fixed. 23. The active Tx message box is now highlighted during a transmission, as in WSJT 4.x. 24. Green ticks marking range of JT65 tone frequencies and red ticks marking shorthand tones may optionally be displayed only if Freeze is checked. (Select on waterfall screen's Options menu.) 25. "Tool-tip" readout of full entry in CALL3.TXT is now provided after Lookup, if mouse pointer hovers over the ToRadio box. 26. Parameter RDsec was removed from the screen, as it is not implemented. 27. Some additional diagnostic information is now displayed. A parameter "ms" following the "Soundcard x.xxxx" readout is a measure of the maximum time between successive servicing of the audio callback routine. The nominal value is about 186 ms, but somewhat larger values are normal owing to granularity of the Windows system clock. Values larger than 330 ms cause a warning message to appear in the console window. Large values of this parameter may be related to audio input problems (see below). 28. The latest version of DL8EBW's CALL3.TXT database is included with the distribution. It will be installed only if there is no file named CALL3.TXT already in your WSJT6 installation directory. KNOWN PROBLEMS -------------- 1. Some fraction of WSJT 5.8.1 users -- perhaps 5-10%, it is hard for me to judge -- have had problems with erratic audio input. I am having difficulty tracing the problem because I have not been able to reproduce it on any computer to which I have access. Typical symptoms are that after startup WSJT 5.8.1 runs normally in Monitor mode for a minute or so, but then the reported audio level jumps to a much higher value and perhaps fluctuates wildly. Two users have switched todifferent sound cards and made the problem go away. Several others have discovered that if they first start WSJT4 and leave it running (in Monitor mode, I believe), and then start WSJT 5.8.1, the new program behaves properly. One user corrected the problem by turning off an "AGC" feature on his sound card. Apparently most of the newer SoundBlaster cards have this AGC feature, and it is turned ON by default. I am told that it can be turned OFF by using the supplied utility CTMIX32.EXE. I do not yet understand the cause of the erratic audio problem. It is possible that it has been fixed in v5.8.3, as several minor changes have been made to the audio input routines; but I think this is unlikely. If you had this problem at your station and have now solved it, please let me know what you did! If you still have problems when running version 5.8.3, let me know about that as well. 2. I do not yet have a good definition of the "minimum computer" required to run WSJT6. Several people have told me that they are using the program successfully on 300-500 MHz machines. Those with computers slower than about 600 MHz will do best to avoid the higher waterfall speeds and not run many other programs while using WSJT. Beta Release 5.8.1 ------------------ Beta release 5.8.1 is an entirely new program, dsesigned to preserve the features and the "look and feel" of version 4.9.8, but also to add many new features and do so in a way that will make for easier for program maintenance and future development. After a period of beta testing, the program will become known as WSJT 6.0. I will refer to it here as WSJT6. Many features of WSJT6 will be familiar to present users of WSJT4.x. However, the user interface and other real-time portions of the program have been entirely re-written, so you may find a few things that look different or work differently than before. WSJT6 is a multi-threaded program. This architecture permits much better timing control and much better sharing of the CPU among the program's many tasks. A real-time waterfall is provided, optimized for each of the WSJT modes. You can measure and set the Rx gain in real time. You can decode FSK441 pings immediately after hearing them. The decoders for JT65 and JT6M are essentially the same as those in recent versions of the program. (I have many plans for enhancements to the decoders, but these must wait for future updates.) The FSK441 decoder has intentionally reverted back to approximately version 3.8.1, because it has been shown that recent versions did not perform quite as well. WSJT 5.8 is a stable release. Extensive tests by a small group of early beta testers have already shown that it works well. However, it contains many thousands of lines of new code, and most likely that code has some bugs. Nevertheless, I think you will find many operational advantages to using it. Over the past 2.5 months, all of my own MS and EME QSOs have been made with the new version. If you decide to participate in the beta testing period, please accept the responsibility of reporting any bugs that you find, as well as telling me of features you would still like to see. I would appreciate hearing about new features that you like, as well. PRELIMINARY INSTRUCTIONS AND COMMENTS ------------------------------------- 1. I suggest installing WSJT6 to a new directory such as C:\Program Files\WSJT6. After installation you will probably want to copy your version of the callsign database, CALL3.TXT, into the new WSJT6 directory, replacing the one that is supplied. 2. When you start the program you should get three windows on your screen. One has a black background and I will call it the "console window"; it is mainly used for debugging messages. You can minimize it and generally ignore it. You should, however, look there for messages if the program crashes (see also items 9 and 11, below). The other two windows are a Spectran-like waterfall and the more-or-less familiar WSJT window. It is no longer necessary or desirable to run Spectran simultaneously with WSJT. 3. FSK441, JT65, and JT6M are all present and functional. I have made many QSOs with FSK441 and JT65, so I know they are working well. JT6M has been tested somewhat less, but I have seen no problems as yet. EME Echo mode and the CWID feature are not yet implemented. 4. To start the real-time spectral display, click Monitor. Normally you can leave Monitor on all the time. 5. There are two ways to set the Rx Audio gain. You can call up the Windows mixer as before, using the "Rx Volume Control" item on the Options menu. There is also a digital gain control near the bottom right of the waterfall screen. You should aim for around 0 dB, as before -- but with 16-bit audio sampling it is no longer very critical. Use the "S-meter" at the lower right of the waterfall display, or the familiar box labeled "Rx noise" at bottom center of the main screen. 6. You should be able to make FSK441, JT65, and JT6M QSOs more or less as usual. In FSK441 and JT6M you will want to run the spectral display at speed "H1" or "H2" (speed is selected at the top of the waterfall screen). (The "H" means horizontal scrolling.) Scrolling speeds "5" and "H2" use a lot of CPU time, so you may want to avoid them unless your computer is pretty fast. I generally use speed "1" or "2" for JT65 and "H1" for FSK441 and JT6M. 7. When running FSK441 in the horizontal scrolling mode, the spectral display shows current data in the top half and the previous Rx sequence in the bottom half. The most recently decoded sequence is shown also on the main screen, as in version 4.x. 8. You can decode FSK441 pings right away by clicking on any of the 2-dimensional spectral displays, or the accompanying green lines. You can click on the top half, the bottom half, or in the main screen's graphical area. 9. If you have more than one sound card, you can select the desired one. Look at the startup messages in the console window. You should see a list of the available Audio devices and information about which one has been selected. If you wish to change the selection, enter the desired device numbers on the Setup->Options screen, then terminate and restart the program. 10. If your display has resolution 1024 x 768 or less, you may prefer to resize the waterfall window so that only its top portion remains visible. The two main WSJT windows may then be kept visible without overlapping. 11. Some program crashes can kill the console window so that you can't read the error messages. If this happens, and if the crash is repeatable, open a Windows Command-Prompt window; CD to your WSJT6 installation directory, and start the program from there by typing "WSJT6". With this startup procedure, any subsequent post-mortems will remain visible. Please report any such messages to me! 12. You may find decoding to be slightly slower than with v4.9.x. I have not yet spent any time optimizing the new code for speed; it will get faster when I turn attention to that task. If you have an older computer you may wish to check the menu item "Setup->Accelerated decoding", which will suspend updating the waterfall during the decoding process. 13. Be sure to look at the screens called up by function keys F1 and Shift-F1. These screens are also available from the Help menu. They list some useful keyboard and mouse commands that you might otherwise overlook. 14. Be sure to explore all the menus and on-screen controls, and try out the commands listed on the help screens. Until I can find time to write a new manual, this is the best way to learn about some of the new features. 15. In JT65 mode, a horizontal green line on the frequency scale shows the range of frequencies that will be searched for a sync tone. You can set the "Freeze DF" value by clicking on the main screen's red curve (as in WSJT 4.x) or by clicking on the waterfall with the shift key held down. If "Freeze" is checked, vertical green ticks will mark the selected sync-tone frequency and the corresponding frequency of the highest data tone. Red tick marks denote the frequencies of the RO, RRR, and 73 shorthand messages. 16. WSJT6 can read and process WAV files produced by earlier versions. The converse is not true, however, because earlier versions of WSJT are not equipped to read the 16-bit data files produced by WSJT6. 17. When you click "Log QSO," a line with date, time, HisCall, HisGrid, frequency, and mode is added to the file WSJT.LOG in the installation directory. 18. Every second, a short file named "c:\azel.dat" is updated with time, moon and sun coordinates, frequency, doppler, and doppler rate information. This file could be used by other software to make your antenna track or your radio follow doppler changes. 19. In the lower left corner of the main screen you will see a message of the form "Soundcard: x.xxxx", where x.xxxx is a number close to 1.0000. This number is the ratio of the soundcard's measured sampling frequency to the nominal value, 11025 Hz. The displayed value should stabilize after the program has been running for a minute or so. If you see values less than about 0.9990 or greater than 1.0010, please let me know about it and tell me what kind of computer and sound card you are using. 20. Callsigns for Swaziland (prefix 3DA0) can now be used in standard JT65 messages, and they will provide the full "deep search" sensitivity. 21. The box labeled "NB" enables a software noise blanker. If your receiver already has a good noise blanker, this may be of little use; if it does not, you may find this one better than nothing. It can be helpful when short, impulsive noise spikes are present. 22. The "QRN" parameter of older WSJT versions has been combined with the "Clip" parameter. In FSK441 mode, Clip=0 corresponds to the old QRN=5. If you want more FSK441 immunity to summertime QRN, increase Clip above 0 just as you would have increased QRN above 5. 23. The "B" and "C" submodes of FSK441 have not been implemented. As far as I could tell, they were little used. Let me call your attention to the online WSJT Forums hosted by DK5YA at www.vhfdx.de/cgi-bin/yabb/YaBB.pl. If you provide information and post questions about WSJT 5.8 there, it will help others as well as yourself -- and may help to reduce the load on my email inbox. I do, of course, want to hear from you directly if you have found a problem with the new program version or suggestions for its improvement. Changes in Version 4.9.8 ------------------------ Version 4.9.8 is a minor maintenance release. The changes are: 1. Bug in JT65 decoder could (rarely) cause a correct decoding by the Reed-Solomon decoder to be "overruled" by an incorrect decoding from the Deep Search decoder. Fixed. 2. Bug in JT65 Reed-Solomon decoder could cause program to crash under certain rare conditions. Fixed. 3. The standard "CQ" message generated for a callsign having an extra prefix or suffix should not include a grid locator. Fixed. 4. Automatically generated CW messages for stations with callsigns longer than 4 characters were improperly truncated. Fixed. 5. Bug in JT65 decoder could occasionally cause one or two extra letters to be appended to a correctly decoded callsign. Fixed. 6. Grid locator entered in "Report" box in FSK441 mode (as used by some in North American meteor scatter contest) would cause a crash on program restart. Fixed. Changes in Version 4.9.7 ------------------------ 1. The only change in version 4.9.7 is to add KC4 to the list of supported DXCC prefixes. Changes in Version 4.9.6 ------------------------ 1. WSJT 4.9.5 fails to decode some files that have relatively high S/N and good Sync level. This is a bug, and has been fixed. For this reason alone, you should definitely upgrade to Version 4.9.6. 2. New optional message formats are provided for conveying and responding to signal reports. It has been permissible for some time to send, for example, VK7MO K1JT -24 K1JT VK7MO R-27 (The number after the minus sign must have two digits and must be in the range -01 to -30.) I plan to implement a quick way of copying the measured strength of a decoded transmission into TX message #2, when desired. This is not yet done in v4.9.6, however. You must edit the TX messages by hand if you use these formats. Enhancements in version 4.9.6 now allow you to send messages like the ones listed below. Both stations will need to be running v4.9.6 in order for these to work: VK7MO K1JT RO VK7MO K1JT RRR VK7MO K1JT 73 3. Decoding by the deep search algorithm has been extended so as to include messages of the types discussed in item 2. Changes in Version 4.9.5 ------------------------ 1. Full support for long callsigns like ZA/PA2CHR and G4ABC/P is now provided. When using such a callsign prefix or suffix, do not include a grid locator in your transmitted message. Note that 4.9.5 and 4.9.2 do not handle prefixes in the same way; they are not compatible. To get the benefit of the expanded capability, both stations (TX and RX) must use 4.9.5. The correct message format is "K1JT V5/ZS5Y" or "V5/ZS5Y K1JT". The extended callsign must be present in CALL3.TXT or in "To Radio" for the deep-search decoder to be effective. 2. If you double-click on a callsign in the decoded text window, and if the word preceding the callsign is "CQ", then TX message #1 will be selected after the messages are updated. Otherwise, TX message #2 will be selected. 3. So that you will be aware of what is happening, the background color in the TX message box turns red whenever a message you have entered is "non-standard" and will be sent as 13 characters of plain text. 4. Items related to decoding have been removed from the Setup | Options screen and replaced by a new menu labeled Decoding. Here you may now select "No shorthands" for FSK441 and several options for JT65 decoding. 5. In case you are upgrading directly from v4.9.0 or earlier to v4.9.5, a callsign database file has been included as CALL3A.TXT. If you do not already have a file CALL3.TXT, you should rename the supplied file to CALL3.TXT. Otherwise, you will probably want to ignore the supplied file, since you will have made additions to your own copy. 6. The frequency of program crashes (for example, after a long period of monitoring) is much reduced, possibly to zero. Please, if you encounter a received wave file that reproducibly causes WSJT to crash, send it to me. Changes in Version 4.9.2 ------------------------ 1. In CW mode you can now set the desired T/R period by using the text box provided. This feature did not work properly in v4.9.1. 2. Under some conditions using the "Add" button to edit information in the file CALL3.TXT would cause a program crash with the message "Run-time Error #53". Fixed. 3. Using the double-mouse-click on a callsign in the decoded text window will now set the active Tx Message to Tx2. I believe this will be most commonly what is desired, and will be an added convenience for random JT65 operation. 4. The "Sked" box remained visible on the EME Echo screen, covering part of the RIT box. Fixed. 5. The program generates two numbers to characterize its level of confidence in decoded messages. In version 4.9.1, these numbers appeared at the end of each decoded text line. They are not displayed in version 4.9.2, but in the next version I will probably display them if you have checked the "Aggressive decoding" box. The first number is 0 or 1 according to whether the soft-decision Reed Solomon decoder has failed or succeeded. The second number represents a confidence level on a 0-10 scale for messages decoded using the "deep search" algorithm. Anything under 3 is questionable; messages rated 6 and above are unlikely to be wrong, unless you are processing "garbage" data containing strong birdies, QRN, etc. In that case, you are on your own. 6. A bug was introduced when implementing the "Aggressive decoding" check box. This bug caused a stray "OOO" flag to be sometimes displayed even when no signal was present and synchronization had not been achieved. Fixed. Changes in Version 4.9.1 ------------------------ 1. A programming error in version 4.9.0 prevented the "deep search" portion of the JT65 decoder from detecting some messages that include the "OOO" signal report. The bug has been fixed, and consequently the extra 4 dB of sensitivity will become available for those messages. 2. The callsign database, a file named CALL2.TXT in version 4.9.0, has been converted to a comma-delimited format and is now named CALL3.TXT. As has been true in the past, you should maintain your own copy of this file according to your own needs. New calls may be added to the file using the "Add" button of WSJT, and you can edit the file directly with the Windows NotePad program. I apologize for the fact that if you have already edited CALL2.TXT extensively, you will need to do so again. The good news is that the programs WSJT, MoonSked (by GM4JJJ) and Tracker (by W7GJ) will now use the same database file, CALL3.TXT. 3. Two new JT65 check boxes have been made available to the user: one labeled "Sked", located on the main screen, and one labeled "Aggressive decoding" on the Setup | Options screen. Check "Sked" to signify that you are trying to work a known station; the deep search decoder will then look only for your own call and the one displayed in the "To Radio" box. Check "Aggressive search" if you want to see all messages found by the deep-search decoder, even if the confidence level is moderately low. Leave this box unchecked if you prefer to see only decoded messages that have been assigned a relatively high confidence. 4. The duration of T/R sequences in CW mode defaults to 60 s if the Band is 50 MHz, 150 s if 432 MHz, and 120 s otherwise. However, an on-screen box now allows you to override the defaults and set any desired T/R period (in seconds). Changes in Version 4.9.0 ------------------------ On the outside WSJT version 4.9.0 looks nearly the same as its recent predecessors. A "CW" entry now appears on the Mode menu. This is presently a "transmit only" mode: it sends standard EME-style messages at 15 WPM, by keying an 800 Hz audio tone, and it takes care of the timing and T/R switching for you. Receiving is left up to you, the operator. For me, this combination makes CW EME QSOs relaxing and enjoyable. Presently the program uses 2.5 minute sequences if you are on 432 MHz, 2 minutes on 144 MHz, and 1 minute on 50 MHz. (If you want to run with 1-minute sequences on 144, set the band indicator to 50 MHz.) Double-clicking on a callsign in either one of the decoded text windows will cause that callsign to be copied into the "To Radio" box. The call will then be looked up in the database and will be inserted appropriately into the transmit message boxes Tx1 and Tx2. This feature is designed to facilitate random JT65 operation by making it easy to call a station you have just copied calling CQ, or responding to your CQ. The most significant program enhancements are those made to the JT65 decoder. It has been transformed into a multi-layered procedure that takes better advantage of the structured nature of JT65 messages and the substantial computing capability that most WSJT users have in their hamshacks. In version 4.9.0, if the initial JT65 decoding effort fails then deeper searches are attempted using an entirely different approach. The result is a net gain of about 4 dB over a wide range of circumstances. My JT65 digital simulator, which has accurately predicted the performance of previous versions of the software, correctly decodes about 50% of simulated Rx files with the v4.7.0 decoder at a signal level of -24 dB. With the v4.9.0 decoder, it correctly decodes more than half of the simulated data files at -28 dB. This very substantial improvement means that JT65's message-averaging facility will be needed much less frequently than with earlier versions of WSJT. Most of the time, if the transmission synchronizes properly, it will also decode properly. You will get better performance from the new JT65 decoder if you understand a few things about how it works. The following is a very brief description; more complete technical details will be forthcoming when I find time to write it all down. JT65 is capable of transmitting and receiving 2^72 (about 5 x 10^21) distinct user messages. Instead of sending the minimum number of 72 information bits needed to to convey any one of those distinct messages, the program actually sends 63 six-bit "symbols" for a total of 378 bits in each transmission. The 302 extra bits comprise the powerful forward error correction (FEC) capability of the JT65 mode, allowing the system to function reliably with signals far below the audible threshold. One of the first tasks of the JT65 decoder is to measure the signal level at each of the 64 data-tone frequencies during each of the 63 data intervals in a transmission. The program must then decide which one of the possible 2^72 messages was most likely the one sent. This procedure is necessarily probabilistic in nature. The best decoder will go as far down into the noise as possible, but it must also know when to give up so that it produces few false decodes. The total of 2^72 distinct messages is far too many to permit each one to be tested individually against the received signal. However, an important characteristic of the Reed-Solomon FEC code used in JT65 is that well-defined mathematical algorithms can be used to direct the decoder toward the most likely candidate messages, based on the available signal information. A mathematical inversion of the code is made possible by the organization of the redundant information contained in the 306 extra bits. The new JT65 decoder goes far beyond the capabilities of normal Reed-Solomon decoders. If the standard decoding procedure fails to produce a high-confidence solution, the program proceeds to search explicitly for each one of a number of messages that it considers likely or plausible on other grounds. Nearly 2^28 (over 250 million) different callsigns can be accommodated in each of the two callsign fields of a JT65 message. Once again, this is far too many to permit an exhaustive search for them all. Consequently, the "deep search decoder" takes the callsigns listed in the file CALL2.TXT (located in the user's WSJT directory) as being the most likely alternatives in the message's second field. A correlation algorithm is then applied to find out if one of these calls and its associated grid locator are present, combined with either "CQ" or the receiving station's callsign in the first field. High-confidence matching of this kind can be accomplished down to about -28 dB on the WSJT scale, in a single transmission, with a very low error rate. The bottom line is that for any arbitrary callsign the new JT65 decoder performs at least as well as the one in WSJT version 4.7.0. Message averaging works just as it did before, and if you are listening in to a "third party" QSO between two other stations, the sensitivity will be the same as in version 4.7.0. However, if a station that is listed in the file CALL2.TXT is calling CQ or is calling you, your sensitivity will be about 4 dB better on average. Please note that the decoder is given no information whatsoever about what station you may be trying to work. Its heart is "as pure as the driven snow," even if you are working a sked. However, the decoder does presume that the callsign of the transmitting station is more likely to be one listed in CALL2.TXT than some other callsign constructed at random. The program always attempts to decode a purely arbitrary message first. Failing that, it will look more deeply in the noise for the presence of a message that includes the callsign of a station listed in the database file. It is no accident that the algorithm just described bears close resemblance to the thought processes (conscious and otherwise) that we use to copy very weak CW by ear. Familiar combinations like CQ and one's own callsign are always easier to dig out of the noise than random combinations of characters. Callsigns that we have seen or heard before are more easily recognized than arbitrary calls generated at random. The new JT65 decoder behaves similarly, except that it is kept fully in the dark about who you are trying to work. All decoders make mistakes, and this one is no exception. Just like a human copying CW, the JT65 decoder has a "grey area" in which it finds a solution but may have only moderate confidence in it. In such cases the decoder appends a "?" to the decoded text, and the operator must make the final decision as to whether the decoding is correct. Be aware that because of the mathematical message structure, incorrect decodings will not just differ from the correct one in a few characters; more likely, they will exhibit a whole incorrect callsign. As you gain experience in recognizing the graphical and numerical indications of proper message synchronization and the effects of "birdies" and other interference, you will become adept at making these decisions when necessary. With added on-the-air experience I will probably be able top reduce the decoder's error rate, as well. A final note: the file CALL2.TXT replaces the file CALLSIGN.TXT used by earlier versions of WSJT. The format has been changed to permit extended callsigns such as those sometimes used by DXpeditions, for example ZA/PA2CHR. The name of the database file has been changed so as not to "break" an earlier version of WSJT that you may wish to keep available. Full support for extended callsigns (i.e., calls with an extra prefix or suffix) is planned for a future version of WSJT. Changes in Version 4.7.0 ------------------------ 1. New feature: WSJT can now be used simultaneously with Spectran on the same computer. You can start Spectran by selecting "Use Spectran for input" on the Setup menu. This feature also allows the user to select the sound card to be used for input. 2. Bug fix: in some circumstances, switching from a JT65 long-format message to a shorthand message did not work properly. Fixed. 3. Bug fix: for operators in the southern hemisphere and longitudes more than 90 degrees east or west, the wrong "Hot spot" was sometimes identified as the best direction for sporadic meteors. Fixed. Changes in Version 4.6.1 ------------------------ 1. Bug fix: I mistakenly shifted the RX data by 2 seconds, rather than the intended 1 s, when changing the DT range. Therefore in v4.6.0 the actual DT range is not -1 to +5 s as stated, but rather 0 to +6 s; moreover, the displayed values of DT are too small by 1.0 s. This has been fixed. 2. New feature: thanks to Akira, JM1SZY, I learned that occasionally a file (or an average of several files) will decode better with the AFC feature turned off. Consequently I have added a checkbox that must be ticked to activate AFC in the JT65 modes. If you can trust the frequency stability of the signal you are receiving, and especially if you are trying to receive a signal at -27 dB or weaker, leaving this box unchecked may yield a slight improvement in decoding. In most cases, especially at 144 MHz and above, I recommend leaving the AFC turned ON. 3. Thanks to Chris, GW4DGU, for pointing out that the Gx series of prefixes is no longer legal for reciprocal license operating in the countries of the UK. The valid prefix series for such operation is now the M-series, i.e., M MD MI MJ MM MU MW. I have changed the prefix table accordingly. Version 4.6 ----------- This is the first full release of WSJT since version 3.0. New users can install Version 4.6 directly, without upgrading from a previous installation. Of course, you can also upgrade from an earlier version in the usual way. All download files can be found on the WSJT home page, http://pulsar.princeton.edu/~joe/K1JT. The new release includes an entirely new "WSJT 4.6 User's Guide." This document is about one third the length of the former "User's Guide and Reference Manual," but contains nearly everything you need to know to use the program. A copy of the new Guide is included in the version 4.6 distribution files. You can also download it directly from http://pulsar.princeton.edu/~joe/K1JT/WSJT_User_460.pdf. Even if you are an experienced WSJT user, you should definitely print and read this document. New features in WSJT Version 4.6 include the following: 1. Improved automatic frequency control in JT65 modes. If you have lost JT65 QSOs because of unstable oscillators, this is for you. 2. The acceptable range for DT in JT65 mode is now -1 to +5 s. This range is a better fit for EME communication than the former -2 to +4 s. It will allow for somewhat greater clock errors before inter-station synchronization fails on an EME path. Note to experienced users: this means that the plotting scale for the "blue curve" now runs from -1 to +5 s. EME signals should normally produce a blue peak near the center of the plot area. 3. When the blue window displaying moon coordinates has been toggled to display coordinates for the DX station as well as the home station, it now displays MaxNR in place of SD. MaxNR is the maximum path non-reciprocity in dB. This effect arises from the combination of spatial polarization shift plus Faraday rotation; it is what causes "one way propagation" between stations that use fixed linear polarization. 4. A facility for generating the file ID.WAV for station identification is now built into WSJT. 5. The "Save Decoded" menu item now saves files with decoded shorthand messages as well as normal messages. 6. JT65 has a new shorthand message "ATT" (for "Attention!"). It is intended as an aid to help two stations find each other by determining the correct DF. 7. Visual aids for evaluating JT65 shorthand messages "by eye" are provided if you click on the sync-tone frequency in the Big Spectrum display. 8. For DXpeditions: a country prefix preceded by "/" may be substituted for the grid locator in a type 1 JT65 message. 9. Alternatively, a signal report of the form "-NN" or "R-NN" may be substituted for the grid locator in a type 1 JT65 message. For example, -24 might indicate that signals were being received at -24 dB. The minus sign is required, and NN must lie between 01 and 30. 10. The receiver noise level reported by Measure mode (the level of the "green line") has been increased by 2 dB to be consistent with levels reported by the other operating modes. Changes in Version 4.5.1 ------------------------ Bug fixes: 1. JT6M did not transmit properly in version 4.5.0 because the program failed to switch its wavefile generator into JT6M mode. Fixed. 2. WSJT consumed a large fraction of CPU time in JT65 mode, even when the program was supposedly doing nothing. Fixed. 3. Monitoring for long periods in JT65 mode would occasionally produce a Fortran "output conversion error". Fixed. 4. Clicking the "Add" button with nothing in the Grid box would cause a program crash. Fixed. Enhancements: 1. In the FSK441 modes, messages longer than 3 nonblank characters and starting with R26, R27, RRR, or 73 are no longer transmitted as shorthand messages. 2. Onscreen labels now indicate active status of the "Save Decoded", "Save All", and "Save text in File DECODED.CUM" features. 3. Small improvements have been made in the decoding of shorthand messages in modes FSK441B and C. 4. Alphabetic characters in message templates (on the Setup | Options screen) are now case-insensitive. Principal New Features in WSJT Version 4.5 ------------------------------------------ 1. The JT65 modes employ an entirely new decoding algorithm that uses "soft decisions" to recover the transmitted message. The message format and Reed-Solomon encoding are unchanged, so the JT65A, B, and C modes are fully compatible with earlier versions. However, the new decoder is more sensitive by slightly more than 1 dB. It is based on software licensed from CodeVector Technologies, LLC, and protected under United States Patent 6,634,007. As usual, however, I am making WSJT freely available for amateur radio use. Changes to the JT65 modes are "under the hood," and except for the improved performance you will find them mostly invisible. The new decoder can be somewhat slower than the one in v4.3.4, depending on details of the received data. 2. Like JT65, FSK441 now provides three submodes. FSK441A is identical to the "classical" FSK441. The two new modes, FSK441B and FSK441C, use the same 4-tone frequency shift keying at 441 baud. However, they use forward error correction (FEC) on a character-by-character basis, to improve message reliability. They also provide shorthand messages which are more robust than the single-tone messages of traditional FSK441. Cross-mode communication will not work: a transmission in FSK441B must be received in FSK441B, etc. FEC information in FSK441B and FSK441C is conveyed by sending additional channel symbols (tones) for each character, using special codes designed to optimize the error rate and sensitivity with very short pings. The additional symbols are redundant when the S/N is high, but they allow recovery from transmission errors when the S/N is low. FSK441A, which provides no redundancy, transmits 3 symbols per character. Modes B and C use 4 and 7 symbols per character, respectively. The raw throughput of user information is summarized in the following table: FSK441A FSK441B FSK441C ---------------------------------------------------------------- Sequential tones per character 3 4 7 User data rate, characters/second 147 110 63 Time for a 12-character message, ms 82 109 190 The shorthand messages in FSK441B and FSK441C use alternating tones at two specific frequencies, as follows: Shorthand Low tone High tone message (Hz) (Hz) ------------------------------ R26 861 1206 R27 861 1550 RRR 861 1895 73 861 2239 Tests with my digital simulator show that shorthand messages in FSK441B and FSK441C are several dB more sensitive than the ST messages of FSK441A. At the same time they give a far lower rate of false positives. With multi-tone messages the sensitivities of the three submodes are nearly the same, but they have different trade-offs. Mode A is 25 percent faster than mode B, but mode B is more accurate and will produce much less on-screen "gibberish". Mode C is about half the speed of mode A but has still stronger FEC code. Parameters of the B and C modes were selected in the expectation that FSK441B might become the mode of choice for meteor scatter work on 144 MHz (and possibly also 222 MHz), while FSK441C will likely prove best at 50 MHz where the pings are longer. These suppositions need to be tested, of course. Experienced WSJT users should have no difficulty making the new modes work. Just select the desired mode from the Mode menu (or use the appropriate hot-key combination), and away you go. Other Changes in Version 4.5.0 ------------------------------ 1. Bug fix: In JT65 mode, if you sent 73s and then started a QSO with a new station, the program would sometimes continue sending the 73 message even though TX message #1 had been checked. This has been fixed. 2. Performance enhancement: Shorthand messages in JT65 were sometimes suppressed because of an apparent low-value Sync detection that produced no decoded message. This has been fixed; there is no longer any need to set your Sync threshold to a higher value when you are expecting to receive a shorthand message. 3. The JT65 "Filter" function has been removed. It was confusing to some, and anyway was generally deemed of little value. The new decoder provides a much better solution. 4. The "suggested report" has been deleted from FSK441 decoded text lines. It is replaced by S/N, the measured signal-to-noise ratio in dB. Note that the familiar "dB" measurement of (S+N)/N is still available, as well. 5. Finer adjustment intervals are provided for "S", the FSK441 ping detection limit. As in earlier version, these numbers refer to (S+N)/N. In contrast, the "Single Tone" or "Shorthand" detection limits refer to S/N, a more useful parameter at very low signal levels. (See below for more details on signal to noise ratios, if interested.) 6. A button labeled "Add" just below the grid locator box will cause the displayed callsign and grid to be entered into the CALLSIGN.TXT database. 7. A date and time stamp is now added to the DECODED.CUM file at program startup or when you first enable writing to this file. Request to Users ---------------- As usual, I will appreciate hearing from users about the new features in WSJT. Let me know, of course, if you find bugs or other problems in the program. In particular, let me know of your experiences with FSK441B and FSK441C. Remember, my guess is that FSK441B should work very well on 2 meters, while FSK441C may work best on 6 meters. After you have gained some experience with FSK441C on 6 meters, I would be interested to know whether you think JT6M should be retired. In North America, at least, I do not think it is being used very much. Why use both S/N and (S+N)/N ? ------------------------------ WSJT has traditionally measured the level of FSK441 signals as the ratio (signal plus noise)/(noise) = (S+N/N), in dB. This quantity is approximately what S-meters try to measure; it has the advantage that it goes to zero when there is no signal, while at high signal levels it increases as you would expect, in proportion to signal strength. At low signal levels, however, the numbers for (S+N)/N in dB behave in a way that may be counter-intuitive. When WSJT reports that a meteor ping had strength 3 dB, it means that signal plus noise was 3 dB higher than noise alone. That means that signal and noise were equal in power, so the corresponding value of S/N must be 0 dB. If the same signal had been transmitted with half the power, it would have had S/N = -3 dB, and (S+N)/N would have been 10*log(0.5+1.0) = 1.76 dB. Yes, cutting the TX power in half would only reduce the ping level from 3.0 dB to 1.76 dB! That's why, for many purposes, S/N is a more useful number -- and why I am now listing both numbers in FSK441 decoded text lines. The table below will allow you to convert easily between S/N and (S+N)/N, both as numerical ratios and as dB. S/N S/N (S+N)/N (S+N)/N (dB) (dB) ---------------------------------------- 10.0 10.000 11.000 10.41 9.0 7.943 8.943 9.51 8.0 6.310 7.310 8.64 7.0 5.012 6.012 7.79 6.0 3.981 4.981 6.97 5.0 3.162 4.162 6.19 4.0 2.512 3.512 5.46 3.0 1.995 2.995 4.76 2.0 1.585 2.585 4.12 1.0 1.259 2.259 3.54 0.0 1.000 2.000 3.01 -1.0 0.794 1.794 2.54 -2.0 0.631 1.631 2.12 -3.0 0.501 1.501 1.76 -4.0 0.398 1.398 1.46 -5.0 0.316 1.316 1.19 -6.0 0.251 1.251 0.97 -7.0 0.200 1.200 0.79 -8.0 0.158 1.158 0.64 -9.0 0.126 1.126 0.51 -10.0 0.100 1.100 0.41 Beta Release 4.3.4 ------------------ Beta Release 4.3.4 of WSJT is now available for free download at the WSJT home page, http://pulsar.princeton.edu/~joe/K1JT. The principal change from version 4.2.1 is to offer three JT65 submodes. The submodes differ in tone spacing and total bandwidth as follows: Mode Spacing Total BW ------------------------- JT65A 2.7 Hz 177.6 Hz JT65B 5.4 355.3 JT65C 10.8 710.6 Note that JT65A is identical to the original JT65. If you want to work people who have not yet upgraded to v4.3.4, be sure to select mode JT65A. Otherwise, be sure to use the same mode that your QSO partner is using. Cross-mode contacts will not work. JT65B should be nearly as sensitive as JT65A, and it will be twice as forgiving of frequency instabilities. On balance, with existing "stock" radios, JT65B will probably be better than JT65A. JT65C is less sensitive by a small amount, perhaps 1 dB, but will be even more lenient on stability issues. By all means experiment with the different submodes, and be sure to let me know your conclusions about them! I am presently inclined to recommend that JT65B should become the "standard" JT65 mode. If this tentative conclusion holds up, future versions of the program may no longer support the A and C modes. Other changes from version 4.2.1 include the following: 1. Further improvements have been made to the JT65 decoding algorithm. These improvements apply to all three submodes. Some wave files that would not decode with v4.2.1 now decode properly, especially in averages over several minutes. 2. The frequency width W of the sync tone (the "red spike") is now measured and displayed in Hz after DF in the main text box. In any of the three JT65 modes, W should be no more than 2-4 Hz under good conditions. Uncorrected frequency drifts, excessive oscillator phase noise, and certain propagation effects can make the width larger. Anything over about about 4 Hz will impair copy in JT65A. Similarly, widths greater than about 7 and 15 Hz will begin to impair copy in JT65B and C, respectively. 3. The utility program CWID.EXE now accepts lower case letters on the command line. It also permits you to specify the audio frequency of the tone in the wave file. You may wish to place the tone at 600 Hz or lower so that it lies well below the tones generated by any of the WSJT operating modes. 4. The "Clip" function has been improved in several ways. The yellow and magenta curves in the Big Spectrum display no longer disappear when Clip > 0. Setting Clip = 3 does hard clipping, as before, but it also blanks out any data regions with average power well above the "baseline" of the green curve. Experimenting with different values of Clip may help you to recover good copy from noisy data. 5. I believe that the text window displays in Monitor mode, and when you are using the Include/Exclude buttons, now function correctly. 6. Minor bug fixes: the program no longer crashes in EME Echo mode if you select "EME Calc | Load | Cancel". The correct "S" value is listed on the status bar in JT6M mode. 7. The program's "Fit and finish" is improved in several not very important ways. WSJT Version 4.2.1 ------------------ Version 4.2.1 contains a number of enhancements and bug fixes, mostly related to the new JT65 mode. Changes from version 4.1.1 include the following: 1.1 Message averaging now works correctly 1.2 Many small improvements to the decoding algorithm 1.3 Decoding speed improved by 50% 1.4 JT65 monitor mode is properly implemented 1.5 TX message can be changed up to t=59 s of preceding RX period 1.6 Switch to a shorthand TX message at any time 1.7 Freeze works properly for shorthand messages 1.8 Decodes with failed FEC (forward error correction) are optionally displayable 1.9 "Garbage filter" provided so that questionable decodes appear only if they contain some recognizable text 1.10 Automatic station ID, as in FSK441 and JT6M modes 1.11 Companion program to generate a CW ID.WAV file is included 1.12 The birdie zapper now works in JT65 mode 1.13 "Clip" function has been reactivated 1.14 F5 help screen updated to reflect JT65 practices 1.15 "OOO" message handled more transparently 1.16 Optional display of Moon Az/El at DX station, replacing Sun Az/El 1.17 Right/Left audio out now works properly 1.18 DT displayed as blank rather than 0.0 for shorthand messages 1.19 No program crash if ToRadio or Grid left empty 1.20 No program crash if attempting to decode 60 s file in JT6M 1.21 All other reported problems causing crash have been fixed +-------------------------------------------------------------+ | Quick Start Guide to Using WSJT version 4 and the JT65 Mode | +-------------------------------------------------------------+ Version 4 of WSJT marks a significant departure in the program's evolution. The list of features is no longer a full superset of those available in all previous versions. In particular, the JT44 mode is gone; it is replaced by a new mode called JT65 that I hope will be a significant improvement for making QSOs via EME and extremely weak tropospheric paths. The procedure for upgrading to version 4 is identical to previous upgrades, with one exception: the setup procedure will install a new program in your existing WSJT directory, but will keep the old version alive as well. The two versions of the program can coexist peacefully. During a testing period you will probably want the older version and JT44 to be available as well. What is different about JT65, compared to JT44? Here's a short list: 1. T/R period 60 s; actual TX audio duration 46.8 s. (Yes, this will put somewhat more stress on your PA. If its cooling is marginal, take appropriate action.) 2. Modulation uses 64 data tones plus a sync tone. 3. Tones are spaced by 2.7 Hz in frequency and 0.372 s in time. The total occupied bandwidth of a JT65 signal is about 180 Hz. 4. Transmissions consist of 63 data tones or "symbols," each carrying 6 bits of information. In addition there are 63 sync symbols for establishing time and frequency synchronization. 5. Software AFC (automatic frequency control) can follow drift rates up to about +/-10 Hz/minute. 6. User messages are tightly "source coded" into 72 bits. 7. Strong FEC (forward error correction) coding is used to mitigate transmission errors. 8. User-level message formats are designed to permit maximum possible efficiency in EME or similar QSOs. A valid message must be be one of three possible types: 1. "Call1 Call2 Grid" or "Call1 Call2 Grid OOO" 2. "RO", "RRR", or "73" (so-called shorthand messages) 3. "any text you want" (up to 13 characters selected from a 42-character alphabet) Instead of a callsign, the first field of a message type 1 may contain "CQ" or "QRZ". Other such "special tokens" may be added later. The available alphabet of characters for message type 3 is: 0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ +-./? 9. Instead of JT44's very effective intra-message averaging of the even, odd, and "last N" characters of a message, JT65 offers even more powerful special shorthand messages for RO, RRR, and 73. These have much higher sensitivity than the other message types. They work reliably down to about -30 dB. If you succeed in exchanging callsigns and "OOO" by means of type 1 messages, you should certainly be able to complete the QSO. 10. Message averaging over subsequent transmissions works as it did in JT44, with one exception. The "OOO" signal report typically used for EME can be appended to message #1 and the message will continue averaging without any need to start over. The presence or absence of "OOO" will be detected if sync is achieved, whether or not full decoding has been successful. 11. Receiving FEC-decoded transmissions takes some getting used to. You will find *much* less gibberish on your screen in JT65 than in JT44. The FEC algorithm has a good idea whether it has succeeded or not, and the program will suppress output unless it is "pretty sure" that it has got the message right. You will discover that when the FEC procedure fails and the program has not realized it, text is occasionally produced looks like plausible (but quite wrong) callsigns or grid locators. You must mentally reject such garbage messages, when they occur. In the small amount of on-the-air testing that JT65 has enjoyed so far, my experience is that that only a few percent of decoded messages are displayed incorrectly. Most of the time, received text is either "letter perfect" or is left blank. 12. You may optionally have the program display text for instances when the decoder in uncertain of its results. Doing so makes use of an "expected message", and you can specify a minimum number of characters thst must match before uncertain text is displayed. By default the expected message is "MyCall HisCall HisGrid" where MyCall is your own callsign, HisCall is the one entered in the onscreen "To Radio" box, and HisGrid is the first four characters of the grid locator in the "Grid" box. 13. At least one design choice used to define the JT65 algorithm is still subject to change. If the 2.7 Hz tone spacing turns out to be problematic because of propagation anomalies or inadequate oscillator stabilities, the spacing could be increased. There are significant advantages to the smaller spacing, however, so I am sticking with it for now. Beta Release 4.1.1 ------------------ +-------------------------------------------------------------+ | Quick Start Guide to Using WSJT version 4 and the JT65 Mode | +-------------------------------------------------------------+ Version 4 of WSJT marks a significant departure in the program's evolution. The list of features is no longer a full superset of those available in all previous versions. In particular, the JT44 mode is gone; it is replaced by a new mode called JT65 that I hope will be a significant improvement for making QSOs via EME and extremely weak tropospheric paths. The procedure for upgrading to version 4 is identical to previous upgrades, with one exception: the setup procedure will install a new program in your existing WSJT directory, but will keep the old version alive as well. The two versions of the program can coexist peacefully. During a testing period you will probably want the older version and JT44 to be available as well. What is different about JT65, compared to JT44? Here's a short list: 1. T/R period 60 s; actual TX audio duration 46.8 s. (Yes, this will put somewhat more stress on your PA. If its cooling is marginal, take appropriate action.) 2. Modulation uses 64 data tones plus a sync tone. 3. Tones are spaced by 2.7 Hz in frequency and 0.372 s in time. The total occupied bandwidth of a JT65 signal is about 180 Hz. 4. Transmissions consist of 63 data tones or "symbols," each carrying 6 bits of information. In addition there are 63 sync symbols for establishing time and frequency synchronization. 5. Software AFC (automatic frequency control) can follow drift rates up to about +/-10 Hz/minute. 6. User messages are tightly "source coded" into 72 bits. 7. Strong FEC (forward error correction) coding is used to mitigate transmission errors. 8. User-level mesage formats are designed to permit maximum possible efficiency in EME or similar QSOs. A valid message must be be one of three possible types: 1. "Call1 Call2 Grid" or "Call1 Call2 Grid OOO" 2. "RO", "RRR", or "73" (so-called shorthand messages) 3. "any text you want" (up to 13 characters selected from a 42-character alphabet) Instead of a callsign, the first field of a message type 1 may contain "CQ" or "QRZ". Other such "special tokens" may be added later. The available alphabet of characters for message type 3 is: 0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ +-./? 9. Instead of JT44's very effective intra-message averaging of the even, odd, and "last N" characters of a message, JT65 offers even more powerful special shorthand messages for RO, RRR, and 73. These have much higher sensitivity than the other message types. They work reliably down to -30 dB and below. If you succeed in exchanging callsigns and "OOO" by means of type 1 messages, you should certainly be able to complete the QSO. 10. Message averaging over subsequent transmissions is intended to work as it did in JT44, with one exception. The "OOO" signal report typically used for EME can be appended to message #1 and the message will continue averaging without any need to start over. The presence or absence of "OOO" will be detected if sync is achieved, whether or not full decoding has been successful. [Note: message averaging is only partially functional in the first beta release of the JT65 mode. I will need some experience with the mode in order to optimize the code here.] 11. Receiving FEC-decoded transmissions takes some getting used to. You will find *much* less gibberish on your screen in JT65 than in JT44. The FEC algorithm has a good idea whether it has succeeded or not, and the program will suppress output unless it is "pretty sure" that it has got the message right. You will discover that when the FEC procedure fails and the program has not realized it, text is occasionally produced looks like plausible (but quite wrong) callsigns or grid locators. You must mentally reject such garbage messages, when they occur. In the small amount of on-the-air testing that JT65 has enjoyed so far, my experience is that that only a few percent of decoded messages are displayed incorrectly. Most of the time, received text is either "letter perfect" or is left blank. 12. The program makes use of what it calls the "expected message". By default this message is "MyCall HisCall HisGrid" where MyCall is your own callsign, HisCall is the one entered in the onscreen "To Radio" box, and HisGrid is the first four characters of the grid locator in the "Grid" box. The AFC algorithm, in particular, can work more effectively when the actual message received matches the expected message. 13. Several design choices used in defining the JT65 algorithm are still subject to change. If the 2.7 Hz tone spacing turns out to be problematic because of propagation anomalies or inadequate oscillator stabilities, the spacing could be increased. About 1 dB of additional S/N could be obtained by omitting the "Grid" field of the standard message format. This would also reduce the maximum "plain text" message length from 13 characters to 10. 14. Please note that the "Clip" and "ST" are not functional in WSJT v4.1.1. Their settings do not affect program operation. Beta Release 3.8.1 ------------------ This release contains the following new features: 1. An optional large spectral display. Its axes are reversed with respect to those of the FSK441 and JT6M waterfall displays; in the new plot, frequency runs from left to right and time from top to bottom. 2. A new birdie zapper that is especially effective in the FSK441 and JT6M modes. You can watch what it is doing by observing the waterfall displays before and after the "Zap" box is checked. Click "Decode" to refresh the displays after checking or uncheking "Zap". 3. Message decoding in FSK441 mode has been improved in several ways. DF is more accurately determined. Better synchronization is achieved with the precise timing of 25-sample tone bursts comprising each message symbol. Folding of messages is no longer attempted. (It seems that whenever a ping is long enough to make folding effective, it's also strong enough to make folding unnecessary.) As in previous versions, the left mouse button allows decoding of single-tone messages while the right button suppresses them. 4. It is now permissible to click "Gen Std Msgs" while transmitting in FSK441 or JT6M mode. When this button is clicked, the Tx message number will reset to #1 if and only if the callsign in "To Radio" has changed. 5. Message formatting templates for FSK441 and JT6M may now include the special codes %G and %L to insert your 4-digit grid or full 6-digit locator, respectively, in the message. 6. "Reset Defaults" now resets the QRN level to 5, as it should. 7. The decoding parameters in use are no longer listed in the Status Bar at lower right. This listing had become redundant. 8. In Monitor mode, the name assigned to the Rx wave file begins with "Mon_" instead of the "To Radio" callsign. 9. In FSK441 mode, all messages with more than 3 non-blank characters are transmitted in multi-tone mode. Beta Version 3.6.4 ------------------ The previous version had the threshold set very low for all mouse-picked decoding attempts in JT6M mode. This was useful to me for testing, but produced excessive gibberish. Version 3.6.4 has a reasonable threshold and produces much cleaner output. In addition, the message averaging algorithm has been improved. I find that I seldom need to use either "Freeze" or "FixAve" now. These buttons are still present in version 3.6.4, but unless I hear that people are finding them useful I may remove them soon. An option has been added to the Setup menu so that you can determine whether you want the "Tx Stop" button to kick you out of Auto Mode, or not. The default is not to do so. ***IMPORTANT*** If you can make WSJT v3.6.4 crash in normal operation, please let me know (and tell me how). Also let me know if you find anything that does not work as intended. I believe the present code behaves well and is nearly ready to be upgraded from "Beta" status to a full release. WSJT Beta Version 3.6.3 ----------------------- Version 3.6.3 has a number of small improvements, many of them not immediately visible. Several bugs have been exterminated. The JT6M decoder works better and is more sensitive. JT6M now has a "FixAve" checkbox; when this is checked, average messages will be sought only at the lengths of the automatically generated messages. WSJT Beta Version 3.6.2 ----------------------- Version 3.6.2 corrects a problem that on a few machines caused a fatal error that could only be corrected by deleting the initialization file, WSJT361.INI. WSJT Beta Version 3.6.1 ----------------------- Version 3.6.1 corrects a problem that caused an immediate termination on program startup on some users' machines (typically older ones). If you need this upgrade, you need it bad! It also fixes a minor bug that could cause a divide-by-zero error if you clicked on the plot area when no data was available to analyze. WSJT Beta Version 3.6.0 ----------------------- The JT6M mode is only a week old, but many hundreds of QSOs have been made with it all over the world. This mode is expressly designed for meteor scatter on 6 meters, but it may be useful with some other propagation modes as well. It has characteristics that place it about midway between FSK441 and JT44 in both speed and sensitivity. A second beta release of WSJT with JT6M, Version 3.6.0, is now available for downloading at http://pulsar.princeton.edu/~joe/K1JT/UPD360.EXE The download file is about 0.75 MB in length. Comparison of Versions 3.6.0 and 3.5.1 -------------------------------------- 1. Version 3.6.0 has a better and faster decoder for JT6M. Further improvements in this area are still to come. 2. Several bugs that could cause crashes in V3.5.1 have been fixed. Version 3.6.0 appears to be quite stable (at least on my own computers). 3. Some buttons have been moved from their familiar positions. 4. Gadgets that Microsoft calls "Up-Down Controls" have replaced the +/- buttons used for various decoding parameters. 5. You can now drag the mouse pointer across any portion of the large plot area to cause decoding of that portion of a recorded file. This works in both FSK441 and JT6M mode. The area you selected is marked when the plot is refreshed. 6. A yellow curve now appears above the green curve in JT6M mode. The yellow line represents measured power received at the sync-tone frequency and in the sync-tone intervals. I haven't yet written up any detailed instructions for the JT6M mode. However, if you are an experienced WSJT user you probably won't need any. Here are a few things it will be helpful to know about JT6M. 1. Like JT44, JT6M uses 44-tone FSK with a "sync tone" and 43 possible data tones -- one for each character in the supported alphanumeric set. The sync tone is at 1076.66 Hz, and the 43 other possible tones are spaced at 21.53 HZ intervals up to 2002.59 Hz. The tones are keyed at a rate of 21.53 baud, so each one lasts for 1/21.53 = 0.04644 seconds. The sync tone is ON during every 3rd transmission interval; tones representing two data characters follow each sync tone. The transmission rate of user data is therefore (2/3)*21.53 = 14.4 characters per second. The transmitted signal sounds a bit like piccolo music. 2. Basic operation is very similar to FSK441. Just select JT6M from the WSJT "Mode" menu (or use "Shift-F7") and then proceed as usual. 3. The green line and waterfall display have their usual meanings. 4. The program attempts to decode both single pings and an "average message". The average is the last line displayed during each decoding attempt, and is flagged with an asterisk as in FSK441. The number to the right of the asterisk is the inferred message length (for example, the number should be 10 for the message "W8WN K1JT "). If the program finds the wrong length, the average will be garbled or meaningless. All message lengths should be even numbers, because odd-length messages are padded with an extra space at transmission time in order to make them even. 5. Clicking with the left mouse button decodes a 4-second block of data near the mouse pointer. The right button uses a longer segment of 10 seconds. Drag the mouse with the button down to select any desired region. Experiment for best decoding as necessary. 6. As soon as you see some properly decoded text, set the DF box to the measured DF and check the "Freeze" box. Alternatively, you can set the Tolerance to a low value (say 25 Hz) after the desired signal has been identified. Use RIT, if necessary, to bring subsequently measured DF's down to a small value. 7. Default settings for the decoder are S > -12 dB, Tol=400 Hz, DF=0 Hz. 8. JT6M can work with signals that are up to 13 dB weaker than those required for FSK441. In the brief on-the-air tests I've made with W8WN, we have both found that mouse-clicking on the smooth green line, even where nothing was heard and nothing can be seen, sometimes causes both callsigns to pop up out of the noise! Version 3.0 ----------- A new major release of WSJT, Version 3.0, is now available for free download. Instructions for upgrading and for complete installations can be found at http://pulsar.princeton.edu/~joe/K1JT. What's new in Version 3.0? -------------------------- 1. The "User's Guide and Reference Manual" has grown to 51 well illustrated pages. The new manual includes four major new sections which together cover: a) the EME Echo mode, including the "Measure" sub-mode and the "EME Calc" utility for estimating the strength of your echoes from the moon; b) the nature of the various astronomical calculations done within WSJT, and a summary of their accuracies; c) several pages describing availability of Fortran source code for the DSP algorithms in WSJT, as well as a suite of test programs for generating simulated data and testing the FSK441 and JT44 encoding and decoding algorithms; d) a short essay on possible future developments for WSJT. 2. The astronomical calculations in WSJT have been overhauled and thoroughly checked. In practice the differences from V2.9 will seem minor, but as described in the new manual's Appendix B, the accuracies of computed positions for the sun and moon, and for the EME Doppler shift, are now well documented. Computed positions are accurate to within about 0.04 degrees, and Doppler is better than 1 Hz at 144 MHz. Exactly what is meant by the displayed data is now described in the manual, as well. 3. A new feature has been added on the Help menu. It pops up a screen summarizing the standard message exchanges used for minimal QSOs using FSK441 and JT44. No more excuses for not being sure about which message you should send next! 4. The Measure mode can now be left running indefinitely, with its output written to a file. A few individuals have been wanting to use the program for radio astronomy purposes, and the new version provides a minimal facility for doing this. 5. The display screen for the EME Calc utility has been cleaned and tightened up. 6. A few other small niceties, all minor in scope. Version 2.9.0 ------------- I am pleased to announce the availability of an upgrade to WSJT Version 2.9. The upgrade provides most of the features of the soon-to-be-released Version 3.0; I am releasing it now as Version 2.9 because many users have asked for early access to its new capabilities. A full release of Version 3.0 must await some updating of the Users Guide and Reference Manual. Probably a few additional features will be added by then, as well. Please be patient! Version 2.9 is available only as an upgrade. As usual, it can be downloaded from the WSJT web site, http://pulsar.princeton.edu/~joe/K1JT, or from the European mirror site http://www.dk5ya.de. New features of the program include the following: 1. EME Echo mode now works on certain computers (generally older, slower ones) that previously refused to run Echo mode properly. The new version runs fine under Windows 95 on my ancient 100 MHz Pentium with 32 MB of RAM. 2. A new feature known as "Measure" can be selected from the main screen in EME Echo mode. Click the Measure button and your system will record the received audio for one second, compute the level of the noise and display the result in units of dB relative to the nominal WSJT "0 dB" level. The program will repeat this measurement cycle every 2 seconds and plot the results as a green line in the graphical screen area. You can use this mode to measure Sun noise, antenna temperature, ground noise, preamp gain, and a host of other useful quantities, relative to a chosen reference level. 3. A pop-up utility labeled "EME Calc" can be selected from the EME Echo screen. It provides an easy way to predict whether you should be able to detect your own echoes from the moon, as well as your ability to work another station by EME. Boxes are provided to enter your TX power, TX feedline loss, RX noise figure, RX feedline loss, antenna gain, ground gain, ground noise, and sky temperature. Similar quantities can be entered for a second station, and you must also specify the operating frequency. When you click "Compute," the program will calculate the maximum expected echo strengths for the "Home Station" and the "DX Station" individually, as well as the maximum expected signal strength of each station at the other location. The program also estimates the averaging time that would be required to detect echoes at the predicted signal level. Signal strengths are quoted relative to the WSJT standard, the noise power in a 2500 Hz bandwidth. If the computed result for your echo exceeds about -38 dB, you have a chance of being able to detect your echoes using WSJT. In comparison, echoes are detectable by the human ear only if they exceed about -14 dB on the same scale, or equivalently +3 dB in a 50 Hz bandwidth. Note that the estimated signal strengths are supposed to be the maximum values expected for the specified conditions. There are many reasons (Faraday rotation, ionospheric scintillation, libration fading, ...) why the actual signal strength may be different, and deviations are much more likely to be downward than upward. The predicted echo strength for my present 144 MHz station at a reasonably good time of the month is around -25 dB. My experience has been that the predictions are fairly good if enough time is spent to be sure of catching a Faraday rotation peak. A number of smaller enhancements have been made in the EME Echo mode of WSJT. These include the following: 4. The program is much better behaved when operating at higher frequencies, in particular 1296 MHz and above. If you fail to enter an RIT setting or specify one that would make the return echo fall outside the audio frequency range 900 - 2100 Hz, the program will suggest a better RIT value for you to use. 5. The amount of programmed frequency spread of your transmitted signal (the "Dither" magnitude) can be set to any value in the range 0 to 500 Hz. It defaults to 50 Hz. 6. Instead of accumulating average echo parameters indefinitely, you can set a parameter "Tavg" that specifies a time constant for averaging. The default value is 5 minutes; at this setting the average echo spectrum will build up as before for the first 5 minutes, but thereafter it will track the signal characteristics over the most recent 5 minutes. In other words, the average gradually "forgets" the signals received more than Tavg minutes ago. Setting Tavg to a large number, say 999 minutes, will closely approximate the program's previous behavior. If you can detect your EME echoes easily and want to see how they vary with time, you might set Tavg to 1 minute, start a "Measure" sequence, and take down the signal level readings at one minute intervals. 7. Information sent to the main text window every 6 seconds now accumulates, with the text window scrolling as necessary. The output is also (optionally) written to file DECODED.CUM so that you can study the data later. Other miscellaneous improvements and bug fixes include the following: 8. In JT44 mode, if the "Grid" box is left empty then no EME Doppler shift will be displayed. 9. The minimum "Dsec" increment has been reduced from 1 second to 0.5 second. This will permit more precise on-the-fly correction of the Windows clock for use by WSJT, should that be necessary. 10. JT44 messages are always exactly 22 characters in length, and any additional characters are ignored. To make this behavior more obvious, any excess characters are now visibly removed from the screen when transmission of a message begins. 11. In Version 2.3.0, hitting the F4 key while in echo mode would cause the program to crash. Fixed. 12. Switching between modes could cause the Auto Period button to be stuck in the disabled or "grayed out" state. Fixed. 13. The last character in a manually edited FSK441 message was not sent if the default trailing blank and "<" character were erased. Fixed. Version 2.3.0 ------------- This release of WSJT is the first to include the EME Echo mode. This mode allows you to detect and measure your own lunar echoes, even if they are far too weak to hear. The mode can be highly useful for evaluating your station performance, even if you prefer to use CW rather than JT44 for your EME QSOs. If you are a present user of WSJT with no interest in detecting and measuring your EME echoes, you will find no significant advantages to upgrading to WSJT Version 2.3.0. With the exception of a minor bug fix, the FSK441 and JT44 modes are essentially unchanged. You can download the upgrade from the WSJT home page, http://pulsar.princeton.edu/~joe/K1JT, and soon also from the European mirror site http://www.vhfdx.de/wsjt. To upgrade an existing WSJT installation of Version 1.9.4 or later you should download and execute the file UPD230.EXE, which will replace your existing files WSJT.EXE and WSJT1.DLL with new files of the same name. I have not yet produced a new full distribution of the latest version. Doing this will require extensions to the User's Guide and Reference Manual, and will probably be accompanied by further improvements to the program. If you wish to do a full installation of Version 2.3.0 from scratch you should download the installation file WSJT222.EXE, run it to install Version 2.2.2, and then upgrade to Version 2.3.0 as described above. Minor Bug Fix: In WSJT Version 2.2.2 and earlier, if you dismissed the "Setup | Options" page by clicking on the "X" in the upper right corner of the form, instead of by clicking the "Done" button, the home station callsign ("My Call") would revert to its default value "K1JT". (Contrary to popular opinion, this was not an subtle ploy designed to increase my own VUCC totals; it was simply a coding mistake.) The bug has now been fixed. EME Echo mode is presently a plain, no-frills implementation. You can activate it from the Mode menu or by striking function key F9. Most of the familiar WSJT buttons will then disappear from the screen, leaving just a few that are essential for controlling the Echo mode. If your station is already operational in the FSK441 and JT44 modes and you have provided the proper signal levels, all you need to do for an echo test is to start WSJT Version 2.3.0, hit F9 to switch to EME Echo mode, aim your antenna at the moon, pick a clear frequency, and toggle Auto Period On. The program will then start cycling through the following loop: 1. Transmit a fixed tone for 2.0 s 2. Wait about 0.5 s for the start of your echo 3. Record the received signal for 2.0 s 4. Analyze and plot the results 5. Repeat from step 1 The loop cycle time is 6 seconds, so the transmitter duty cycle is only 2/6 or 33%. Your transmitter will think it is loafing. At the start of each transmission the frequency of the transmitted tone is randomly dithered by an offset up to +/- 100 Hz around a nominal value of 1500 Hz. The programmed offset is removed from the computed spectrum of each recording before it is added into the accumulating average. This procedure helps to minimize the effect of birdies in the receiver passband: in the average spectrum a fixed-frequency birdie will be smeared out over a 200 Hz range, while the desired signal remains sharply defined. Two curves are plotted in WSJT's main plot area during each pass through the Tx/Rx loop. Each represents the spectrum of received power over a 400 Hz range centered on the expected echo. The curve in gray is a reference spectrum that you can use to be sure you have chosen a reasonably birdie-free passband. It is aligned so as to remove the EME doppler shift computed at the start of your run. The alignment will not be subsequently adjusted for changes in doppler shift or for the random dithering of the transmitted frequency. Stable birdies will therefore stay fixed in the blue spectrum, making them easy to recognize and evade if necessary. The red curve displays the desired EME echo signal. Spectra computed for each 2-second receive period are shifted to correct for changing doppler shift and for the programmed frequency dithering, and are then averaged. The EME echo should appear as a narrow spike near the middle of the red curve, close to DF = 0. In addition to the graphical display, a line is presented in the WSJT text window in the following form: N: 16 Sig: -26.3 dB DF: -1.3 Hz Width: 0.7 Hz Q: 9 This information gives the number N of Tx/Rx cycles that have been averaged, the mean signal strength in dB, the measured frequency offset of the detected echo from the expected frequency, the spectral width of the echo, and a relative quality indicator for the detection on a 0 - 10 scale. Signal strength is measured in the same units as used in the FSK441 and JT44 modes, i.e., in dB relative to the received noise power in a 2500 Hz bandwidth. Low values of Q represent dubious detections, in which case the values of signal strength, DF, and width may be meaningless. A note about doppler calculations will be helpful here. Most computer programs in amateur EME stations use approximate formulae to compute the position and distance of the moon and the expected doppler shifts of echos. WSJT is no exception, and I cannot presently quote a firm figure on the accuracy of its doppler calculations or describe how their errors depend on lunar coordinates or the accuracy of your station location. EME Echo mode uses a calculated doppler shift to align received spectra so that the echo should appear at DF = 0. I have found that on 2 meters the return signals generally fall within 10 Hz of DF = 0. Further improvements in accuracy of the doppler routine will be forthcoming. If you can hear your own EME echoes you should see a spike in the red curve within a few seconds after toggling Auto Period On. If your echoes are 10-15 dB below the audible threshold you should see a significant spike on the red curve within a few minutes. To give you a better example of what to expect, consider the parameters of my station. On 2 meters I run up to 400 Watts to a 17.6 dBd antenna (4 x 9 el yagis) aimed at the horizon. I have never heard my own CW echoes with this system. However, when the moon is in my elevation window at 0 - 10 degrees I can easily detect my echoes at any time of the month using WSJT in its EME Echo mode. Indeed, I can turn off the PA and use my FT-847 barefoot, delivering 35 W to the antenna, and still detect my echoes rather easily, even with the moon in a "bad" part of the sky and the path degradation as large as -8 dB. I seem to be able to detect my echoes reliably down to relative signal levels around -36 dB. The spectral analysis done in EME Echo mode provides a frequency resolution of 0.67 Hz. If your transmitter or receiver has short-term frequency stability much worse than this value, so that something drifts or wobbles by more than about 1 Hz in 2 seconds, your echo sensitivity will be degraded. Most modern radios have no difficulty in meeting this standard on the 6 and 2 meter bands, but the higher UHF and microwave bands will be more problematic. I don't have enough experience to know what the spectral width of an echo on the 432 MHz or 1296 MHz band should be after averaging for a few minutes. I have been measuring widths of 2 Hz or less on 2 meters. By default WSJT will assume that your receiver and transmitter are tuned to the same frequency. An on-screen box labeled "RIT (Hz)" is provided so that you can inform the program of any offset receiver tuning, for example to accommodate a large doppler shift. Suppose you are running a test on 70 cm and the predicted doppler shift at the start of the run is -1087 Hz. That would cause echoes from the 1400 - 1600 Hz transmitted audio tone to come back as low as 313 Hz, probably well below the low-frequency cutoff in your receiver's passband. Use your transceiver's RIT control to offset the receiver tuning by some round number within a few hundred Hz of the predicted value -- say -1000 Hz in this example -- and enter this offset in the RIT box before starting the echo measurement. The program will accommodate subsequent changes in the doppler shift up to 800 Hz or so, if necessary, without any further adjustments. Your echo should appear at the center of the red curve, as usual. You won't need to use the RIT feature on 6 or 2 meters, where doppler shifts are much smaller and echoes always fall well within the receiver's SSB passband. Please note that I have so far tested the EME Echo mode only on 2 meters. You will discover that the software implementation is not yet highly polished; a number of improvements are already in the works, but I want to gain the advantage of feedback from other users before I go too much further. If you use the EME Echo mode -- especially on bands other than 2 meters -- please send me your comments, experiences, and suggestions! I am anxious to know how well it works for you. Version 2.2.2 ------------- This is a minor maintenance release. As usual, you can download it from the WSJT web page, http://pulsar.princeton.edu/~joe/K1JT. In addition to a short update file, UPD222.EXE, a full distribution of WSJT Version 2.2.2 is available as WSJT222.EXE. I had thought that Version 2.2.1 had already fixed a sometimes baffling bug appearing in earlier versions: if WSJT was terminated when in its "minimized" state, it could get "stuck" on your Windows taskbar and refuse to return to a full size display. It's not always easy for me to test program revisions on all available versions of Windows, and it seems that the V2.2.1 fix did not solve the problem on at least some versions of Windows 98. This time, with V2.2.2, I believe it's *really* fixed! If WSJT is stuck in the minimized state you should fix it as follows, and then upgrade to Version 2.2.2: A) Start WSJT. It should appear in minimized form on the taskbar at the bottom of your screen. B) Right-click on the WSJT taskbar label and select "Move". C) Press the "left arrow" and/or "up arrow" keys a few times and then move the mouse. You should start to see a "dotted frame" indicating the location of the WSJT screen. D) Click the left mouse button, and you should be back in business. Then you should download and install UPD222.EXE and upgrade your system to Version 2.2.2. Version 2.2.1 ------------- This is a minor maintenance release. You can download it from the WSJT web page, http://pulsar.princeton.edu/~joe/K1JT. In addition to the short update file, a new full distribution of WSJT Version 2.2.1 is available, as well as a new version of the manual addressing the new program features. As always, I will be pleased to receive comments and suggestions at email address k1jt@arrl.net. Please note, however, that I will be on vacation and not reading email from July 7 through 21. Version 2.2.1 fixes the following minor bugs in Version 2.2.0: 1. When first started without a valid INI file, the v2.2.0 would fail to "Generate Std Messages" when asked to do so. Once you have switched modes, say from FSK441 to JT44, the program worked correctly. 2. Local hour angles greater than 180 degrees are now displayed as negative angles. 3. If you did not check the menu item "File | Save text in File DECODED.CUM", the v2.2.0 would create an unwanted file named "fort.21" and write all decoded JT44 text there. 4. If WSJT was terminated when in the "minimized" state, it could get "stuck" on your Windows taskbar. If you are stuck in this mode you should fix it as follows, and then upgrade to Version 2.2.1: A) Start WSJT. It should appear in minimized form on the taskbar at the bottom of your screen. B) Right-click on the WSJT taskbar label and select "Move". C) Press the "left arrow" and/or "up arrow" keys a few times and then move the mouse. You should start to see a "dotted frame" indicating the location of the WSJT screen. D) Click the left mouse button, and you should be back in business. Version 2.2.0 ------------- WSJT Version 2.2.0 provides several significant enhancements, a number of smaller improvements, and four minor bug fixes. To upgrade to v2.2.0 you should download the self-extracting zip file UPD220.EXE and execute it to extract its contents, directing the resulting files to your WSJT installation folder. The new version includes the following changes: 1. The JT44 mode now has an adjustable parameter called "Clip." It can be controlled with +/- buttons just below analogous ones for the "Sync" parameter. The value of Clip defaults to 0, where it has no effect. By increasing Clip to 1, 2, or 3 you can introduce "soft," "moderate," or "hard" clipping of any sudden increases in signal strength that might ruin the decoding of an otherwise usable signal. I have found that setting Clip to 2 or 3 permits me to use JT44 in the presence of summertime QRN that renders v2.0.1 useless. Clipping also helps to accommodate occasional meteor pings in a JT44 QSO, recovering the program's ability to synchronize on a weak residual signal. You can leave the clipping turned on; note, however, that using hard clipping on a signal that does not require it can cost you about 1 dB in message S/N. I recommend generally leaving Clip set to 0 and increasing it only when necessary. 2. JT44 mode has a new checkbox labeled "Zap Birdies." It does just what you would hope such a command would do -- and it can turn a totally spoiled signal into good copy! (In the upgrade file I've included an example wave file recorded via EME from W7FG, in the presence of a strong birdie at my station. To become a believer, try decoding this file both with and without "Zap Birdies" checked. He was sending me the message "K1JT W7FG EM26 ".) The Zap algorithm works best with birdies that are steady in both amplitude and frequency. A sure indicator that you have a birdie problem is a persistent extra spike (or spikes) in the red-line plot, in addition to the one corresponding to the JT44 sync tone. If the birdie is higher in frequency than the sync tone by 20 to 465 Hz, you will probably see a number of identical garbage characters in the line of decoded text. If this happens, check the "Zap Birdies" box and hit "Decode Again", and your copy should improve. It will work best if you have already identified the correct value of DF and checked the "Freeze" box to lock onto the Sync tone. Do not expect miracles! Keeping birdies out of your receiver or QSYing to avoid them will always work better than trying to deal with them in software. Nevertheless, this birdie-killer can make the difference between a successful QSO and one that fails miserably. 3. The JT44 mode has a second new checkbox labeled "Fold Msg." For messages having identical content in the first and second half, this feature can yield a signal-to-noise improvement of 1.5 dB. The JT44 default message formats have been modified slightly to maximize the opportunities for useful message folding. For example, if K1AA is working G2ZZ, the first EME-style message will now be generated as "G2ZZ K1AA G2ZZ K1AA ". (Notice the two spaces in the middle of the message and at the end.) If the "Fold Msg" box is checked, the message will be decoded simply as "G2ZZ K1AA ". Try decoding a marginal signal both with and without the "Fold Msg" box checked. QSB conditions might make one or the other preferable at a particular time. 4. In WSJT versions 2.0.0 and 2.0.1 the JT44 decode algorithm produces a single-character average of the last four character positions in a message. In Version 2.2.0 the averaging limit has been changed to equal the number of "O" characters (for EME messages) or "R" characters (for non-EME messages) at the trailing end of default TX message #2. For example, if clicking "Generate Std Texts" produces "G2ZZ K1AA OOOOOOOOOOOO" for message #2, the program will produce a single-character average based on the last 12 received character positions. This choice gives you the best possible chance of properly decoding an "O" or "R" report in message #2, and it also gives you a good chance at snagging the "RRRRRRRRRRRRRRRRRRRRRR" message under very marginal conditions. For steady signals the procedure can yield a 5.4 dB S/N advantage over single characters and a 2.4 dB advantage over the four-character average. 5. WSJT now remembers whether you were using FSK441 or JT44 mode when you last exited the program. On startup it restores the most recently used mode, including values of W, S, and Sync, as appropriate. 6. All decoded text in JT44 mode is now written to the cumulative file DECODED.CUM. In previous versions of WSJT, text was saved only in FSK441 mode. 7. The default Sync setting in JT44 mode is now 1 rather than 2. I believe nearly everybody runs with Sync = 1. 8. WSJT v2.2.0 is more complete and more consistent about saving information about the starting directory and the form size of the "File | Open" dialog box. 9. The displayed azimuths for "Hot A" and "Hot B" (direction headings to use for optimal sporadic meteor reflections) now wrap correctly at 0 and 360 degrees. You will no longer see, for example, values like 368 or -8 degrees if you are working someone to your north. 10. In JT44 mode the program now displays the local hour angle of the Moon, in degrees. You will appreciate this if you have a polar mounted EME array. 11. The UTC Offset may now be specified as a floating-point number -- that is, with significant digits after a decimal point. 12. The count of available records displayed in the average message window behaved illogically when "Decode Again" and "Include" were used. This has been fixed. 13. There was a bug in the JT44 display routine that caused error messages to appear when the moon's right ascension was very close to 00:00. The error could appear at most once a month, and it would persist for an hour or so. The bug has been fixed. 14. There was an apparent logical inconsistency in program behavior if "Exclude" was clicked after "Clear Avg" had been executed. This has been fixed. 15. In V2.0.1 if you hit F8 more than once and then hit F7, the "Width" parameter in FSK441 mode would be set to 200 ms. This has been fixed. Version 2.0.1 ------------- This is a minor maintenance release. Principal changes from Version 2.0 include the following: 1. The installation scripts for both the full installation and the upgrade to v2.0.1 are more robust and much easier to use. 2. The decoding parameters for FSK441 mode are saved correctly after you have used JT44 mode. 3. The controls for "Decode Again", "Include", and "Exclude" are now fully available during the Tx period. 4. Certain colors (e.g., the backgrounds of a few labels) now display better on older machines. 5. The background colors behind certain Tx messages in JT44 mode have been corrected. 6. The manual has been updated to conform with the new installation scripts, and a number of other small changes (mostly correcting typos) have been made. 7. The Tab key now moves the focus between various on-screen controls and text boxes in a rational way. Version 2.0 ----------- A major new release of WSJT, Version 2.0 is now available for free download. Instructions for upgrading and for new installations can be found at http://pulsar.princeton.edu/~joe/K1JT. What's new in Version 2.0 ? -------------------------- The JT44 mode for extreme weak signal work was first introduced in beta release 1.8.0. This mode has now matured, the program is stable, and tons of EME QSOs (among others) are being made with it. New features and fixes in Version 2.0 include the following: 1. Full monitor mode with separate averaging of 1st and 2nd sequences. 2. Mouse-selected value of DF for decoding when "Freeze" is checked. 3. Program is much faster at certain critical points, and now runs reliably on a 75 MHz Pentium with 24 MB of RAM. 4. The dreaded "always starts minimized" bug has been fixed. 5. Certain dates (such as "2002 VIII 21" now display properly in machines configured for European format. 7. A number of other small niceties.