WSJT 4.7 User's Guide - THE DK5YA VHF-PAGE
Contents
1. background temperatures See also Band menu T R Period set length of T R intervals for FSK441 and JT6M modes in seconds Fast CPU decode JT65 signals immediately after a recording has finished Check this box only if your computer is fast enough to allow decoding in 5 seconds or less It permits you to see a decoded message before your next transmission begins No Sh disable all decoding of shorthand messages in FSK441 Other Setup Items File Setup Mode Save Band Help Options F2 Set COM Port Ctrl P Generate ID WAY DTR v RTS v Use Spectran For input Adjust RX volume control Adjust TX volume control Alternate graphical pointer Alternate PTT Logic TX Mute F3 Enter new To radio call sign F4 TX Stop Forces Auto OFF Set COM port set number of the COM port that will activate T R switching To disable COM port T R switching enter 0 Generate ID WAV create a CW wave file in the WSJT home directory with My call sent at 25 WPM 440 Hz DTR RTS select the serial port signal line that will control your T R switching sequence 13 Use Spectran for input run Spectran simultaneously with WSJT sharing the sampled audio For additional instructions see Appendix B Adjust RX TX Volume controls display sound mixer controls Alternate graphical pointer use arrow instead of crosshairs as the mouse s graphical pointer Alternate PTT Logic activate slightly2. and right mouse buttons and observe the decoded text that appears Click the Big Spectrum button to see what these signals look like on the large waterfall display Click Erase on the main screen to clear the text and graphical areas Next select JT6M from the Mode menu and open the sample file from AF40 Nothing decodes automatically in this file the signal is very weak but try right clicking on the green line at about t 12 9 s as displayed on the green label at lower left of the plot area You will find that AF40 was calling KIJT Try listening to this file the signal is audible some of the time but only barely Finally switch to JT65A mode and open the recording from OH7PI The graphics window and decoded text boxes on your screen should look like the picture on page 5 Listening to this file you will hear only random noise OH7PI s 144 MHz EME signal was much too weak for CW communication at this time but he was solid copy in JT65 Adjusting Signal Levels 1 Turn on your radio and tune it to a clear frequency so that only background noise is sent to the sound card Press F9 to select the EME Echo mode Select Setup Adjust RX Volume control to bring up the sound card input mixer Click Measure to start a sequence of noise measurements Adjust a slider on the audio mixer and or your receiver gain control s so as to bring the signal level close to what WSJT calls 0 dB The signal level is displayed numerically and ill
3. different program logic for controlling your T R switching via the COM port A few combinations of hardware and operating system drivers seem to work better with this option checked Tx Mute mute the transmitter Use with Auto ON to monitor one side of a QSO Enter new To radio callsign clear the To radio and Grid boxes in preparation for new entries Tx Stop forces Auto OFF if this item is checked clicking TX Stop during a transmission will toggle Auto to OFF Mode File Setup Mode Save Band Help FSK441A F7 FSK441B Shift F7 FSK441C Ctrl F7 Select desired operating mode from this menu JT6M Shift Ctr F7 JT65A FB v 31658 Shift F8 JT65C Ctrl F8 EME Echo F9 Save Save Decoded save any files producing decoded text in subdirectory RxWav under your WSJT home directory Save All save all recorded files in subdirectory RxWav of your WSJT home directory Band Select your operating band from displayed list The selected frequency is used for computing EME Doppler shifts and sky background temperatures Help Help displays a brief message urging you to download and read the WSJT 4 6 User s Guide the manual you are reading now About WSJT displays version and copyright information Which message should I send Choosing this item or using shortcut F5 will pop up a text box with reminders about the standard message sequences used for minimal QSOs with FSK441 JT6M and JT65 14 Alphabetical List of On
4. loop 1 Transmit a fixed tone for 2 0 s 2 Wait about 0 5 s for start of return echo 3 Record the received signal for 2 0 s 4 Analyze average and plot the results 5 Repeat from step 1 At the start of each transmission the frequency of the transmitted tone is offset randomly around a nominal value of 1500 Hz A number in the text box labeled Dither Hz controls the magnitude of the random offset The observed spectrum of each echo is shifted by the dither amount before being accumulated into the average This procedure is very effective in minimizing the impact of birdies in the receiver passband In the average spectrum a fixed frequency birdie is smeared out over a wide range while the desired signal remains sharply defined aol File Setup Mode e Help DF Hz Width Q EME Echo mode 15 1 1 27 3 16 1 0 26 8 17 0 8 27 0 18 0 8 27 2 19 0 8 26 1 20 0 7 26 3 gt 21 0 6 26 3 22 0 6 26 5 Measure Erase Clear Avg RIT Hz jo Echo Dither Hz 150 Tavg min 5 FEL KKK KS oo oo oo 6 o 48 38282 Two curves appear in the graphical area after each T R cycle each one representing the spectrum of received power over a 400 Hz range centered on the expected echo frequency The blue lower curve is a reference spectrum that you can use to be sure you have chosen a birdie free passband Itis aligned to remove the Doppler shift computed at the start of the run and not subsequentl
5. small circle to the right of the message text In the FSK441 and JT6M modes and for shorthand messages in JT65 you can switch messages while a transmission is in progress by clicking on one of the TX buttons to the right of the circles Operating Hints After every decoding attempt WSJT displays its best estimate of a detected signal s frequency offset The accuracy of these estimates is approximately 25 Hz for FSK441 signals 10 Hz for JT6M and 3 Hz for JT65 Within these tolerances and subject to the stability of oscillators and the propagation path you should see consistent numbers in the DF column during any QSO producing usable signals In the FSK441 and JT6M modes if DF lies outside the range 100 Hz it will help to retune your receiver to compensate Do this with the RIT control or by using split RX TX VFOs In general you should not change your transmitting frequency during a QSO since your partner will be trying to tune you in at the same time JT65 is tolerant of frequency offsets up to 600 Hz and unless the red spike is close to one edge of the plot area see picture on p 5 retuning with RIT is optional However note that EME QSOs on bands above 432 MHz can have Doppler shifts of several kHz or more In such cases you will certainly need to use RIT or split VFOs in order to acquire the received signal Once the program has synchronized on a JT65 signal it s best to click on the red spike check Freeze and red
6. your power amplifier You can use a class C amplifier without generating unwanted sidebands or splatter Please note that full amplitude 11 transmissions lasting 30 seconds or longer will put more stress on your final amplifier than SSB or CW operation If this would cause the amplifier to overheat you should take appropriate action reduce power or add another cooling fan or blower Menus and the Setup Options Screen File WSIT4 by K1IT File Setup Mode Save Band Help Open Ctrl O Open Next in Directory F6 Decode All Files in Directory Shift F6 Delete Files in RxWav Ctrl F2 Save Text in File DECODED CUM Delete File DECODED CUM Ctrl F3 Exit Open read and decode a previously recorded file stored on disk The file must be a standard wave file recorded in 8 bit monaural format with 11025 Hz sampling Open Next in Directory read and decode the next file after one already opened Decode All Files in Directory sequentially read and decode all wave files following the one already opened Delete files in RxWav delete all wav files in the RxWav subdirectory Save text in file DECODED CUM append decoded text to a file named DECODED CUM in the WSJT installation directory Delete file DECODED CUM erase the cumulative text file Exit terminate the program Setup Options see screen picture on p 2 My call Enter your callsign Grid locator Enter your 6 digit grid locator UTC offset your
7. 5_141605 Fie position 5s RX noise 1 dB W gt 40 S gt 2 1 Sh gt 2 GQRN 5 Tol 400 opone Station Parameters Main Screen ID Interval m Min 0 000 Right Max 1 000 Both My call KIJT FSK441 amplitud n k cae None FSK441A mode Grid locator FN20qi A 1 000 Change on UTC offset fo B 7 000 Sane RX delay s 0 2 1 000 Audio Output TX delay s 02 D 1 000 Left 0 FSK441 JT6M message templates Freq MHz NA defaults EU defaults NA 144 TAT eT M lt zM MyCall T R Period gt Setup Options T To Radio FSK441 2 T R M RYR lt XA Report JTEM Screen 2G Grid4 30 1X3 R6R lt saa Everything else sent as is TX4 RRR lt Fast CPU TX5 7E I NoSh Taste Ica M lt Example Files To gain some familiarity with the operation of WSJT use the program to decode some example files provided with the standard installation Hit function key F7 to choose FSK441A mode and select Open from the File menu Navigate to the RxWav Samples folder in your WSJT home directory and open the file recorded from W8WN When this file has been decoded the top of your screen should look like the picture on page 2 With a speaker or headphones connected to the soundcard output listen to the recording by clicking the Play button You will hear static crashes at the beginning of the file and a moderately strong ping from W8WN about 18 seconds later Try clicking around the ping with both left
8. IM SO S2 S5 S7 S9 SM SP ST SU SV SV5 SV9 T2 T30 T31 T32 T33 T5 T T8 T9 TA TAIL TF TG T TI9 TI TK TL IN TR TT TU TY TZ UA UA2 UA9 UK UN UR V2 V3 V4 V5 V6 V7 V8 VE VK VKO VK9 VP2 VP5 VP6 VP8 VP9 VQ9 VR VU VU4 VU7 XE XF4 XT XU XW XX9 XZ YA YB YI YJ YK YL YN YO YS YU YV YVO Z2 Z3 ZA ZB ZC4 ZD7 ZD8 ZD9 ZF ZK1 ZK2 ZK3 ZL ZL7 ZL8 ZL9 ZP ZS ZS8 17 Appendix B WSJT and Spectran Spectran is a program written by Alberto di Bene IZ2PHD and Vittorio De Tomasi IK2CZL It provides real time spectral analysis with a waterfall display as well as many other useful features Starting with version 4 7 of WSJT and version 2 build 213 of Spectran the two programs are aware of each other and can be used simultaneously on the same computer The current version of Spectran is now included with the WSJT installation and upgrade packages Instructions for Spectran can be found in the file Spectran pdf which is included with the WSJT distribution To start Spectran from within WSJT select menu item Setup Use Spectran for input This will start the Spectran program in its WSJT mode and in its compact view As long as Use Spectran for input remains checked WSJT will obtain its audio input via Spectran Note that Spectran allows you to select the sound card to be used for input If you have made sure that Spectran runs pr
9. Screen Controls Note some controls are visible only in certain operating modes Add causes the displayed callsign and grid locator to be added to the database file CALLSIGN TXT If an entry for this callsign already exists you will be asked if you want to replace it AFC activate automatic frequency control in JT65 decoding algorithm Auto toggles ON or OFF timed sequencing of transmit and receive periods Big Spectrum display large waterfall spectrogram for most recently decoded file Time increases from top to bottom frequency from left to right This display can help you to identify different types of signals and noise distinguish wanted signals from birdies etc Brightness adjust brightness of waterfall spectrogram FSK441 and JT6M only slider below large graphics area Click Decode to see effect of change Clear Avg erase text in average message box and clear message accumulator Clip normally set to zero Increase its value to 1 2 or 3 to apply soft moderate or hard clipping to a signal before attempting to decode its message May be useful to reduce the effects of static crashes etc Contrast adjust contrast of waterfall spectrogram FSK441 and JT6M only slider below large graphics area Click Decode to see the effect of a change Custom Standard Texts toggles between two sets of TX messages Custom texts can be used to store messages such as grid locator or contest information Decode analyze most re
10. WSJT 4 7 User s Guide Copyright 2004 by Joe Taylor K1JT WSIJT is a computer program for VHF UHF communication using state of the art digital techniques It can decode signals propagated by fraction of a second reflections from meteor trails as well as steady signals more than 10 dB weaker than those needed for conventional CW or SSB Operating Modes e FSK441 for high speed meteor scatter e JT6M for meteor ionospheric scatter on 6 meters e JT65 for extremely weak troposcatter and EME e EME Echo for detecting your own echoes from the moon System Requirements SSB transceiver and antenna for one or more VHF UHF bands Computer running Microsoft Windows 200 MHz or faster CPU 32 MB of available RAM Monitor with 800 x 600 or higher resolution Windows compatible sound card Computer to radio interface using a serial port to key your PTT line or use VOX Audio connections between transceiver and sound card A means for synchronizing the computer s clock to UTC Quick Start Installation and Setup 1 aa Nn Download WSST from http pulsar princeton edu joe K1JT or the European mirror site http www vhfdx de Execute the downloaded file to install WSJT to a directory of your choice If you have not already done so print a copy of this manual and keep it handy Connect appropriate interface cables between your computer and radio For help with the hardware interface refer to one of the many descriptions of other so
11. and decoding parameters Sun Moon Data current coordinates of sun and moon and EME path information Click anywhere in this box to display lunar coordinates for the DX station and MaxNR the maximum non reciprocity of the EME path caused by spatial polarization and Faraday rotation Click again to toggle back to the normal display Tavg min sets averaging time in EME Echo mode To radio callsign of station being called Text entered in this box becomes leading part of recorded file names Appendix A Supported Country Prefixes If you are operating under the licensing authority of another nation you can substitute the portable country prefix preceded by for your grid locator in the standard JT65 type 1 message The supported three character country prefixes are listed below 1A 1S 3A 3B6 3B8 3B9 3G 3C0 3D2 3DA 3V 3W 3X 3Y AJ 4L 4S 4U1 4W 4X 5A 5B 5H 5N 5R 5T 5U 5V 5W 5X 52 6W 6Y 0 7P 1Q IX 8P 8Q 8R 9A 9G 9H 9J 9K 9L 9M2 9M6 9N 9Q 9U 9V 9X 9Y A2 A3 A4 AD AG AT A9 AP BS7 BV BV9 BY C2 C3 C5 C6 C9 CE CEO CE9 CM CN CP CT cCT3 CU CX CY0O CY9 D2 D4 D6 DL DU E3 E4 FA EA6 EA8 EAS E EK EL EP ER ES ET EU EX EY EZ F FG FH FJ FK FM FO FP FR FT5 FW FY H4 H40 HA HB HBO HC HC8 HH HI HK HKO HL HM HP HR HS HV HZ G9 IS T9 J2 J3 J5 J6 J7 J8 JA ID JT JW JX JY K KG4 KHO KH1 KH2 KH3 KH4 KH5 KH6 KH7 KH8 KH9 KL KP1 KP2 KP4 KP5 LA LU LX LY IZ M MD MI MJ MM MU MW OA OD OK OH OHO OJO OK OM ON OX OY OZ P2 P4 PA PJ2 PJ7 PY PYO PZ RIF R
12. and receiving stations By default the frequency search range is 400 Hz 600 Hz in JT65 You can reduce the range by setting the value of Tol for tolerance to a lower value Several other decoding parameters can be adjusted as well In FSK441 mode W sets the minimum width and S the minimum strength in dB for acceptable pings Adjustments can be made at any time by clicking on spinner controls next to the parameter labels and all parameters can be reset to default values by clicking the Defaults button WSIT4 by K1IT E zoj x Fie Setup Mode Save Band Help JT6M mode 0 f Time s AC5TM_030309_175601 28 0 1 2 ee te EI ww Tu igh aE l oyrar eld E pe l 4l i 17 5601 8 0 0 6 4 31 WB4ECR In addition to the green line for overall signal strength JT6M produces a yellow line showing the detected strength of a synchronizing tone JT6M attempts to decode both individual pings and an average message based on the entire transmission or selected portions thereof An average message is flagged with an asterisk at the right end of the text line Clicking with the left mouse button decodes a 4 s block of data near the mouse pointer while the right button decodes a 10 s segment You can also drag the mouse pointer with the 4 button down to select any desired region As in FSK441 with marginal signals you should experiment as necessary for best decoding JT6M can work with signals many dB weaker than those req
13. cently recorded or opened file perhaps after one or more decoding parameters such as Freeze Tol Zap AFC or Clip have been changed Defaults reset parameters W S Sh Sync Clip Tol and QRN to default values Dsec adjust UTC clock reading in 1 s increments to manually resynchronize with UTC or with your QSO partner s computer In general it is best to keep the Windows clock set accurately and Dsec set to zero EME Cale activate the EME signal level calculator Erase clear all information in main text box and graphical areas Exclude remove most recent recording from the average message accumulator Use this option when you are sure that the program has synchronized incorrectly for example because DF and or DT differ substantially from expected values and you wish to avoid contaminating the average message with bad data Freeze search only frequencies within Tol Hz of target DF set by clicking on red spike Gen Std Msgs generate standard messages also reset TX message to and Tol to 400 Hz Include if signal level is greater than 32 dB add most recent recording to average message accumulator even if Sync is less than stated threshold Lookup search database file CALLSIGN TXT for entry in To radio If callsign is found the station s grid locator is retrieved and used to calculate distance azimuth elevation and Doppler shift 15 Measure initiate a series of noise power measurements Monitor star
14. dy tones at one of the four standard FSK441 frequencies 882 1323 1764 or 2205 Hz Tx 1 6 transmit selected message Transmission will continue until the end of the present TX sequence or if Auto is OFF for the duration listed in the T R Period box TX First check this box if you want to transmit during the first period of the timed T R cycle Uncheck it if your QSO partner is transmitting in the first period In this context first is defined as transmitting during the first T R interval of an hour TX Stop terminate a transmission in progress W set the minimum width of pings considered for automatic decoding Zap filter out birdies narrowband signals of approximately constant amplitude before attempting to decode Main Screen Text Boxes Average Text displays average messages in JT65 mode Decoded Text displays decoded messages and other signal information Dither Hz sets maximum random offset applied to transmitted tones in Echo mode 16 Grid after a successful Lookup displays the six digit grid locator of the callsign in the To radio box You can also enter a grid locator manually If only four digits of the locator are known add a space Report enter the signal report you wish to send to the other station then click Gen Std Msgs RIT Hz your receiver RIT setting in Hz Status Bar panels at the bottom of the WSJT screen for displaying information such as file name file position RX audio level
15. e tight time synchronization so they provide no information on DT The ATT message for Attention is intended to help two stations find each other before a normal QSO begins If a message starts with ATT RO RRR or 73 the shorthand format will be sent If it satisfies the requirements for message type 1 the full message of up to 22 characters will be compressed and sent With any other entry 13 characters of arbitrary text will be sent Standard QSO Procedures Difficult contacts become easier if you follow standard operating practices For minimal QSOs the recommended procedure is as follows 1 Ifyou have received less than both calls from the other station send both calls If you have received both calls send both calls and a signal report If you have received both calls and a report send R plus your signal report If you have received R plus signal report send RRR If you have received RRR that is a definite acknowledgment of all of your information the QSO is officially complete However the other station may not know this so it is conventional to send 73s or some other conversational information to signify that you are done Shir ea Slightly different procedures may be used in different parts of the world or in the different operating modes Typing the F5 key will cause WSJT to pop up a screen that reminds you of the recommended procedures Select the message for your next transmission by clicking in the
16. er from your receiver Click it and your system will record audio for one second compute the level of noise power and display the result in dB relative to WSJT s standard level This cycle is repeated every 2 seconds with the results plotted as a green line and summary data displayed in the large text box If the file DECODED CUM has been activated from the File menu data will be written into that file as well tagged with the Modified Julian Date on which you made the measurements 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 Be sure to disable the receiver AGC if you intend to use the mode for quantitative measurements It would also be wise to make some test measurements for example using a calibrated attenuator to confirm that the reported dB readings are reliable in your system as configured 10 File Setup Mode 5 Help 58 DF H2 N Level Sig DF With Measure mode with preamp turned on and off repeatedly Clear Avg EME Calc Clicking the button labeled EME Calc at the lower left of the Echo mode screen will pop up a utility program for predicting the strength of your echoes from the moon Enter the requested quantities for your station and click Compute if you enter parameters for a DX station as well you will see the maximum strengths for both station s self echoes and for each signal at the o
17. ft keying at 2 7 baud The lowest tone at 1270 5 Hz is used to establish time and frequency synchronization it is switched on for half of the time according to a pseudo random on off pattern The remaining tone intervals carry the user message using a Reed Solomon code for forward error correction The three JT65 submodes all use the same code and modulation scheme but the spacing between tones is different approximately 2 7 5 4 and 10 7 Hz for modes A B and C respectively A transmission in one submode must be received in the same submode If the equipment and propagation path are stable enough that the measured width of the sync tone is consistently 4 Hz or less JT65A will be about 1 dB more sensitive than mode B and 2 dB more sensitive than C Shorthand JT65 transmissions consist of alternating tones each lasting 1 486 s The lower of the two frequencies is always at the sync tone frequency 1270 5 Hz and the separation between tones is given in the following table Message JT65A JT65B JT65C ATT 26 9 Hz 53 8 107 7 Hz RO 53 8 107 7 Hz 215 3 RRR 80 8 161 5 323 0 73 107 7 215 3 430 7 EME Echo Mode EME Echo mode see picture on next page is designed to help evaluate the performance of your station for moonbounce communications Activate it from the Mode menu or by pressing function key F9 Aim your antenna at the moon pick a clear frequency and toggle the Auto button to ON The program will then start cycling through the following
18. h is protected under United States patent 6 634 007 for noncommercial purposes within WSJT Many users of WSJT have contributed in important ways to the program s development Shelby Ennis W8WN ran many dozens of schedules with me during the development FSK441 and JT6M and likewise Jack Carlson N3FZ for JT65 I learned that if Shelby and Jack can t make a program crash most other users won t be able to either Many other users far too many to name individually provided extremely helpful criticisms suggestions and feedback I should particularly mention Lance Collister W7GJ who has never tired of saying in effect surely you can still get us one more dB All of these efforts are greatly appreciated 18
19. n use in Hz Since two way Doppler shift depends on the other station s location as well as your own the Doppler field is blank if the Grid box is empty In EME Echo mode the displayed Doppler is your own self echo value Tsky gives the galactic background temperature in the direction of the moon scaled to the operating frequency and dB the added signal loss at the moon s present distance relative to perigee Dgrd is an estimate of the total signal degradation in dB relative to the best possible time when the moon is at perigee and in a cold part of the sky Click with the mouse anywhere in the light blue text box to see the local coordinates Az and El of the moon at the DX station s location and the maximum non reciprocity of the EME path in dB Click again to toggle back to the normal display Distinctions between the Submodes Messages are encoded differently in the three FSK441 submodes so a transmission in one mode must be decoded using the same mode FSK441A uses a zero redundancy code in which characters are transmitted with three successive tones each at one of four assigned frequencies The FSK441B and C modes use sequences of four and seven tones respectively with the additional information providing error correcting capabilities FSK441B can correct any single error in the four symbols that make up a character while FSK441C can correct up to three errors in seven symbols JT65 transmits messages using 65 tone frequency shi
20. operly by itself on your computer it should run correctly with WSJT as well Further Reading 1 A separate WSJT 4 6 Technical Manual in preparation provides technical specifications and details on how the WSJT modes work The Technical Manual will be posted at http pulsar princeton edu joe K1JT the WSJT home page when available 2 In the meantime technical information can be found in the Version 3 0 WSJT User s Guide and Reference Manual which is still available at http pulsar princeton edu joe K1JT WSJIT300 PDF 3 The first WSJT mode FSK441 was described in OST for December 2001 in an article starting on p 36 4 JT44 a predecessor to the JT65 mode was described in QST for June 2002 in The World Above 50 MHz p 81 Acknowledgments An earlier version of this manual was co authored with Andy Flowers KOSM I started over for the current version but many remnants of Andy s hard work remain Bob McGwier N4HY goaded me into learning something about error correcting codes and Phil Karn KA9Q helped me to understand some of their subtleties Particular thanks are due to Ralf Koetter and Alexander Vardy authors of a research paper entitled Algebraic Soft Decision Decoding of Reed Solomon Codes This paper introduced me to the powerful decoding algorithm now used in the JT65 modes Through their company CodeVector technologies Koetter and Vardy granted a license to adapt their computer code whic
21. ower tone at 861 Hz and the upper at 1206 1550 1895 or 2240 Hz JT65 messages are more constrained and must have one of three basic formats 1 Four alphanumeric fields with specific contents as described below 2 Any arbitrary text up to 13 characters 3 Special shorthand messages ATT RO RRR and 73 The four fields of a type 1 message usually consist of two legal callsigns an optional grid locator and the optional signal report OOO CQ or QRZ can be substituted for the first callsign and CQ may be followed by a space and three digits to indicate a desired callback frequency If K1JT transmits on 144 140 and sends CQ 113 KIJT FN20 it means that he will listen on 144 113 and respond there to any replies A country prefix preceded by or a signal report of the form NN or R NN may be substituted for the grid locator For example 24 might indicate that signals were received at 24 dB The minus sign is required and NN must lie between 01 and 30 A list of supported country prefixes is given in Appendix A The following are all examples of legal messages of type 1 FOHS K1JT FOHS K1JT FN20 F9HS K1JT FN20 OOO FOHS K1JT OOO FOHS K1JT KP4 F9HS K1JT KP4 OOO VK7MO KIJT 24 K1JT VK7MO R 26 CQKIJT CQ K1JT FN20 CQ 113 KIJT CQ 113 K1JT FN20 QRZ K1JT QRZ K1JT FN20 The JT65 shorthand messages are powerful because they can be decoded at signal levels some 5 dB below those required for standard messages They do not us
22. ransmitter are tuned to the same frequency An on screen box labeled RIT Hz allows you to inform the program of any offset receiver tuning for example to accommodate a large Doppler shift Suppose you are running a test on 23 cm and the predicted Doppler shift at the start of the run is 1400 Hz In that case the 1500 Hz transmitted audio tone would be detected at 100 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 the predicted Doppler shift or a nearby rounded value and enter this offset in the RIT box before starting the echo measurement The program will track subsequent Doppler changes up to about 800 Hz if necessary without any further adjustments Your echo should appear near 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 within the transceiver s SSB passband The frequency of a valid echo should be well defined and stable If you click Clear Avg to start a new measurement the echo signal the red spike should build up again at the same DF To be absolutely sure that you are seeing you own echo offset your transmitter frequency by a known amount say 50 Hz while holding the receiver frequency constant A valid echo will shift by the same 50 Hz Measure Mode A button labeled Measure provides a means for measuring relative noise pow
23. s periods while JT65 always uses 60 s intervals To prepare for making a QSO enter the other station s callsign in the To radio box and click Lookup and Gen Std Msgs to generate a sequence of commonly used messages If Lookup does not find the callsign in the database file CALLSIGN TXT you may enter the grid locator manually Decide whether you or the other station will transmit first and check or uncheck TX First appropriately Click Auto to start an automatic sequence of transmission and reception intervals At the end of each receiving period WSJT displays various properties of a received signal graphically A green line illustrates signal strength vs time and other lines or images display spectral information and synchronization results depending on the mode Decoded text appears in the large box near center screen Refer to the pictures on pages 2 4 and 5 for examples in the FSK441 JT6M and JT65 modes When an FSK441 or JT6M reception period has finished the program looks for signal enhancements produced by short lived reflections from meteor trails You can often hear such pings when they occur and they can be seen as spikes on the green line and brighter colors in the waterfall spectrum One or more lines of decoded text may result from each ping By clicking on the green line with the mouse you can force decoding of a particular spot in a record WSSJT attempts to compensate for relative mistuning between transmitting
24. sulting graphical display includes red and blue lines along with the green line The additional curves summarize the program s attempts to synchronize with the received signal a necessary step toward decoding the message Proper synchronization is indicated by a sharp upward spike in the red curve and a broader peak on the blue curve Horizontal locations of the peaks correspond to the frequency and time offsets DF and DT between transmitter and receiver EME QSOs have propagation delays of about 2 5 s and can have significant Doppler shifts Along with clock and frequency errors these effects contribute to the measured values of DT and DF Message Formats Standard messages in FSK441 and JT6M are generated with the aid of templates defined on the Setup Options screen see p 2 Default templates are provided conforming to standard practice in North America and Europe and you can edit the templates to suit your own requirements Normal FSK441 and JT6M messages can contain any arbitrary text up to 28 characters The supported character set is 0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ plus the space character FSK441 provides a special shorthand format to transmit a few simple messages in a highly efficient way Check Sh Msg to activate shorthand messages The supported messages are R26 R27 RRR and 73 FSK441A sends pure tones at 882 1323 1764 or 2205 Hz to convey them while FSK441B and C use alternating two tone sequences with the l
25. t a series of recordings perhaps to monitor a calling frequency or to copy two other stations engaged in a QSO Play play most recently decoded file through sound card speaker output This button functions much like the Play button on a cassette recorder QRN adjust to higher values default 5 to suppress false decodings caused by atmospheric noise Record start recording audio noise from radio The program will record for the time entered in T R Period or until you press Stop If Auto is ON recording will stop when the present T R interval is finished the data will then be plotted and decoded This control works much like the Record button on a cassette recorder S set minimum increase in signal that will be accepted as a ping Save Last save most recently recorded file See also Save Decoded and Save all on the Save menu Sh set minimum strength in dB of an acceptable FSK441 shorthand message Sh Msg enable transmission of FSK441 shorthand messages R26 R27 RRR and 73 Stop terminate a Record Monitor or Play operation This control functions much like the Stop button on a cassette recorder Syne set synchronizing threshold default 1 for the JT65 decoder Tol set decoder tolerance in Hz to frequency offsets When DF has been established and reduced to a small value by retuning the receiver decrease the value of Tol to reduce the probability of false decodings Tune A B C D generate stea
26. ther location Clicking Now will enter the frequency of the active band as specified on the Setup Options form and the sky background temperature at that frequency You can Save a set of parameters to a file and Load a saved parameter set at some later time PS EME Caicutator byer OOOO zimizi A Home station B DX station TX power W 500 50 TX feedline loss dB li Ee Ui RX noise figure dB 08 Sea 0 8 RX feedline loss dB 04 sve pa Antenna gain dBi 19 7 19 7 Ground gain dB 0 0 3 0 Sidelobe noise K 150 Freq MHz 150 EME Calc Tsky K Now 361 144 361 dB Moon dB 0 4 0 4 DGRD dB ly a7 Tr K 79 0 79 0 Tsys K 590 0 590 0 Echo A RxB Echo B RxA S N in 2500 Hz BW dB 20 4 27 4 24 4 17 4 S Nin 50 Hz BW dB 3 4 10 4 7 4 0 4 Predicted echo strengths assume that your specified parameters are reliable everything is working right and Faraday rotation is cooperating if relevant There are many reasons why your actual echo strength at a given time may be less than the predicted value and a few reasons why it might briefly be slightly greater Amplifier Considerations WSJT sends a single frequency sine wave at any instant when it is transmitting Except during station identification there is no key up time signal amplitude is constant and one tone changes to the next one in a phase continuous manner As a result WSJT does not require a high degree of linearity in
27. timezone offset from UTC in hours Enter a negative value if you are east of Greenwich RX delay enforce specified delay between end of transmission and start of next recording TX delay enforce specified delay between activation of PTT line and start of first audio tone sent to transmitter ID Interval set time in minutes between automatic station identifications A value of zero disables the automatic identification To use this feature you must provide an audio file named ID WAV in the WSJT home directory The file can identify your station using any desired mode e g voice or CW See Generate ID WA V 12 NA EU Defaults insert default templates for generating standard FSK441 and JT6M messages The templates can be edited for example to append a suffix or prefix to a callsign or to properly format a contest exchange For example if G4FDX changes the template for message TX1 to read T W9 M the message K1JT W9 G4FDx will appear in the box for TX message when he presses Gen Std Msgs to call K1JT FSK441 Amplitudes set relative voltage to be generated for each FSK441 tone If necessary one or more of these numbers can be decreased from the nominal 1 0 to compensate for nonuniform frequency response in your TX audio system Audio output select which audio channel carries signal from the sound card to the radio Left Right or Both Freq MHz nominal frequency in MHz used for computing Doppler shifts and sky
28. uce Tol to 100 Hz or less In subsequent decodings WSST will search a range of frequencies only Tol Hz around the DF selected by clicking on the red spike Question marks in displayed JT65 text lines indicate OOO and shorthand messages about which there could be some doubt These occur when the OOO flag has apparently been found but the full message text not decoded or when a probable shorthand message is detected but you have not yet checked Freeze and reduced Tol to 100 Hz or less Operator skill is required in order to make the best possible use of JT65 shorthand messages Visual aids to decoding shorthand messages by eye are provided if you click on the sync tone frequency in the Big Spectrum display You will need a method of setting your computer clock to an accuracy of one second or better and keeping it set Many operators use an internet clock setting program while others use a GPS or WWVB receiver Solar and Lunar Data The light blue text box in JT65 and EME Echo mode presents data for tracking the moon measuring sun noise tuning your receiver and evaluating EME path losses The information includes azimuth and elevation Az and El for the sun and those quantities plus right ascension RA declination Dec and local hour angle LHA for the moon All coordinates are in degrees except for RA which is given in hours and minutes The moon s semi diameter SD is given in arc minutes and Doppler shift for the band i
29. uired for FSK441 You will sometimes find that clicking on a smooth green line even where nothing was heard and nothing can be seen causes callsigns or other information to pop up out of the noise Sync tone detected Time synchronization at DF 43 Hz at DT 3 2 s red line blue line DF 600 400 200 0 600 Hz DT 1 0 1 2 5 s T 0 10 20 60 s WSJT4 by K1JT loj x File Setup Mode Save Band Help Graphics Window Sun Moon Data Pe ie OTE OH7PI_031122_104600 Kl1JT OH 7PI KP32 desl A FielD Sync dB 104600 6 20 Decoded Text Box 104600 1 l l KlJT OH PI KP32 1 Monitor Play Stop Save Last Decode Erase Clear Avg Include Exclude JT65A TX First 7 To radio Grid 6 digit Defaults Ea a Average INSBLZ EL29ew sme 1 e a Text Box Zap NSBLZ K10T FNZ0 000 ya _ Lookup _ Add Clip 0 Freeze Was a 1x3 1384 mi 2227 km Tol 400 are ome We Az 245 RRR Tx4 Gen Std Msgs Big ma lt Dsec 0 _ Auto is OFF_ 20 34 55 g KiJT FN20 e Te DT 3 2 DF W 43 2 PX noise 0 48 me Sync gt 1 Clip 0 Tol 400 7 TX Messages Main Screen g JT65A mode JT65 requires tight synchronization between transmitter and receiver so in this mode the only way to initiate a transmission or reception interval is by toggling Auto to ON As in other WSJT modes an incoming signal is analyzed after a full receiving sequence is complete The re
30. und card modes such as PSK31 To start the program double click on the desktop icon for WSJT Select Options from the Setup menu see picture on next page and enter your callsign grid locator and UTC offset Click Done to dismiss the Options screen Select Setup Set COM Port and enter the number of the serial port you will use for T R control Enter 0 if you will use VOX control Indicate on the Setup menu whether you wish to use the DTR or RTS line for PTT control If not sure check both These settings should be adequate for learning your way around the program If you are new to WSJT work through the examples at the top of page 3 and then continue reading this manual stopping to experiment with the program when it seems appropriate Aix File Setup Mode Save Band Help 0 W a Time s WEWN_010809_110400 1 File ID T width dB S N DF Receiving Freq kHz 110400 18 5 640 11 11 155 Z50 TNX Q50 TNX Q50 TNX 050 TNX 050 TNX Decoded Text Box Recor Monita Flay Stop i D Erase FSK441 A IX First V To radio Grid 6 digit wH 40 Defaults Sh Msg M fas Kr lt W8wN EM77bq s421 o ESOR e mei Zap T 96 weuny 26 K1dT 2626 lt EL 8 Lookup Add Sh H 2 as hoe lt EA T 632 mi 1017 km Tol 400 Eston ao Az 257 Hot A 244 Hot B 270 aPN H 5 P2004 Mars c ma Tune Gen Std Msgs Big 73 s e m Al Bl Auto is OFF Spectrum Dsec 0 co K1dT lt c jive Eo File W8WN_04030
31. ustrated by a green line in the plot area The green curve should be approximately aligned with tick marks on the left and right border 6 Press F7 to enter FSK441A mode 7 Click Record to start a receiving period The program will record noise for 30 seconds and then attempt to decode it This should produce a jagged green line in the large plot area along with a waterfall style spectrogram The green line is a graph of received noise power vs time The waterfall is a time vs frequency spectrogram in which frequency increases upward time to the right 8 Select Setup Adjust TX Volume control to bring up the sound card output mixer 9 Turn off your final amplifier if any Click one of the four Tune buttons A B C or D to be sure that T R switching works and an audio tone is sent from the computer to your radio 10 Adjust the slider on the audio mixer to get the proper audio signal level for your transmitter Watch the transmitter power output while sending each of the four tones A B C and D Variations of 10 or even 20 among the four tones are acceptable but 50 differences will degrade your signal You may find it useful to experiment with the setting of a speech processor or ALC control ed nama Basic Operating Instructions Note further details on commands in boldface may be found in the alphabetical list starting on page 15 WSST uses timed intervals of transmission and reception By convention FSK441 and JT6M use 30
32. y adjusted for changes in Doppler or the programmed dithering of transmitted frequency Stable birdies therefore stay fixed in the blue curve making them easy to recognize The red curve displays the average echo signal adjusted to correct for changing Doppler shift and for the programmed frequency dithering Your echo should appear as a narrow spike near the middle of the red curve close to DF 0 Information in the text box gives the number N of completed echo cycles the average Level of receiver background noise in dB the average echo strength Sig in dB its measured frequency offset DF in Hz after correction for Doppler shift its spectral Width in Hz and a relative quality indicator Q on a 0 10 scale Background noise level is given with respect to the nominal 0 dB level used for all WSJT modes Signal strength is measured in dB relative to the noise power in the full receiver passband nominally 2500 Hz Q 0 means that an echo has not been detected or is very unreliable in which case the values of DF and Width are meaningless and Sig is an upper limit Larger values of Q imply increasingly believable echo measurements If you can hear your own lunar echoes you will see a large spike in the red curve within a few seconds after toggling Auto ON If your echoes are 15 to 20 dB below the audible threshold you should see a significant spike on the red curve within a few minutes By default EME Echo mode assumes that your receiver and t
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