WSJT-X User Guide

WSPR mode, including coordinated automatic band-hopping and a new two-pass decoder that can decode overlapping signals.

EME-motivated features including JT4 (submodes A-G), Echo mode, and automatic Doppler tracking. The JT4 decoder is more sensitive than that in the latest WSJT, and message averaging is fully automated. (Note that submodes JT65B and JT65C are also present in Version 1.6, but the high-sensitivity decoder required for EME with JT65 is not yet included.)

Tools for accurate frequency calibration of your radio, so you can be always on-frequency to within about 1 Hz.

Mode-specific standard working frequencies accessible from the drop-down band selector.

A number of corrections to the Hamlib library, fixing balky rig-control features. A few unreliable features peculiar to particular radios have been removed.

Install WSJT-X into its own directory rather than in the conventional location C:\Program Files\WSJTX. Suggested installation directories are C:\WSJTX or C:\WSJT\WSJTX.

All program files relating to WSJT-X will be stored in the chosen installation directory and its subdirectories.

Logs and other writeable files will normally be found in the directory C:\Users\<username>\AppData\Local\WSJT-X.

The built-in Windows facility for time synchronization is usually not adequate. We recommend the program Meinberg NTP (see Network Time Protocol Setup for downloading and installation instructions) or Dimension 4 from Thinking Man Software.

WSJT-X expects your sound card to do its raw sampling at 48000 Hz. To ensure that this will be so when running under recent versions of Windows, open the system’s Sound control panel and select in turn the Recording and Playback tabs. Click on Properties, then Advanced, and select 16 bit, 48000 Hz (DVD Quality).

You can uninstall WSJT-X by clicking its Uninstall link in the Windows Start menu, or by using Uninstall a Program on the Windows Control Panel.

32-bit: wsjtx_2.2.159_i386.deb

64-bit: wsjtx_2.2.159_amd64.deb

32-bit: wsjtx-2.2.159-i686.rpm

64-bit: wsjtx-2.2.159-x86_64.rpm

Use the Mac’s Audio MIDI Setup utility to configure your sound card for 48000 Hz, two-channel, 16-bit format.

Use System Preferences to select an external time source to keep your system clock synchronized to UTC.

To uninstall simply drag the WSJT-X application from Applications to the Trash Can.

Select your radio type from the drop-down list labeled Rig, or None if you do not wish to use CAT control.

Alternatively, if you have configured your station for control by DX Lab Suite Commander, Ham Radio Deluxe, Hamlib NET rigctl, or OmniRig, you may select one of those program names from the Rig list. In these cases the entry field immediately under CAT Control will be relabeled as Network Server. Leave this field blank to access the default instance of your control program, running on the same computer. If the control program runs on a different computer and/or port, specify it here. Hover the mouse pointer over the entry field to see the required formatting details.

Select OmniRig Rig 1 or OmniRig Rig 2 to connect to an OmniRig server running on the same computer. Note that OmniRig is available only under Windows.

Set Poll Interval to the desired interval for WSJT-X to query your radio. For most radios a small number (say, 1 – 3 s) is suitable.

CAT Control: To have WSJT-X control the radio directly rather than though another program, make the following settings:

PTT Method: select VOX, CAT, DTR, or RTS as the desired method for T/R switching. If your choice is DTR or RTS, select the desired serial port (which may be the same one as used for CAT control).

Transmit Audio Source: some radios permit you to choose the connector that will accept Tx audio. If this choice is enabled, select Rear/Data or Front/Mic.

Mode: WSJT-X uses upper sideband mode for both transmitting and receiving. Select USB, or choose Data/Pkt if your radio offers such an option and uses it to enable the rear-panel audio line input. Some radios also offer wider and/or flatter passbands when set to Data/Pkt mode. Select None if you do not want WSJT-X to change the radio’s Mode setting.

Split Operation: Significant advantages result from using Split mode (separate VFOs for Rx and Tx) if your radio supports it. If it does not, WSJT-X can simulate such behavior. Either method will result in a cleaner transmitted signal, by keeping the Tx audio always in the range 1500 to 2000 Hz so that audio harmonics cannot pass through the Tx sideband filter. Select Rig to use the radio’s Split mode, or Fake It to have WSJT-X adjust the VFO frequency as needed, when T/R switching occurs. Choose None if you do not wish to use split operation.

Soundcard: Select the audio devices to be used for Input and Output. Usually the Mono settings will suffice, but in special cases you can choose Left, Right, or Both stereo channels.

Save Directory: WSJT-X can save its received audio sequences as .wav files. A default directory for these files is provided; you can select another location if desired.

AzEl Directory: A file named azel.dat will appear in the specified directory. The file contains information usable by another program for automatic tracking of the Sun or Moon, as well as calculated Doppler shift for the specified EME path. The file is updated once per second.

To add a new message to the list, enter the desired text (up to 13 characters) in the entry field at top, then click Add.

To remove an unwanted message, click on the message and then on Delete.

You can reorder your macro messages by using drag-and-drop. The new order will be preserved when WSJT-X is restarted.

Logging: Choose any desired options from this group.

Network Services: Check Enable PSK Reporter Spotting to send reception reports to the PSK Reporter mapping facility.

UDP Server: This group of options controls the network name or address and port number used by a program that will receive status updates from WSJT-X. Cooperating applications like JTAlert use this feature to obtain information about a running WSJT-X instance.

To change an existing entry, click to select it, type a desired frequency in MHz, and hit Enter on the keyboard. The program will format your frequency value appropriately and add a band designator.

To add a new entry, right-click anywhere on the frequency table and select Insert. Enter a frequency in MHz in the popup box and select the desired mode (or leave the Mode selection blank). Then click OK. The table may include more than one frequency for a given band.

To delete an entry, right-click it and select Delete.

Click the Reset button to return the table to its default configuration.

For a simple setup approach you might want to delete any unwanted bands — for example, bands where you have no equipment. Then click on a Frequency entry and type Ctrl+A to “select all,” and drag-and-drop the entries onto the Station Information table. You can then add any transverter offsets and antenna details.

To avoid typing the same information many times, you can drag-and-drop entries between the lines of the Station Information table.

When all settings have been configured to your liking, click OK to dismiss the Settings window.

Click the Stop button on the main window to halt any data acquisition.

Select JT9 from the Mode menu and Deep from the Decode menu.

Set the audio frequencies to Tx 1224 Hz and Rx 1224 Hz.

Select Tab 2 (below the Decode button) to choose the alternative set of controls for generating and selecting Tx messages.

Bins/Pixel = 4

JT65 …​. JT9 = 2500

Start = 200 Hz

N Avg = 5

Palette = Digipan

Flatten = checked

Select Cumulative for data display

Gain and Zero sliders set near midscale

Use the mouse to adjust the width of the Wide Graph so that its upper frequency limit is about 2400 Hz.

Select File | Open and select the file ...\save\samples\130418_1742.wav. When the file opens you should see something similar to the to the following screen shot:

Double-click on either of the decoded lines highlighted in green. This action produces the following results:

Double-click on the decoded message “K1JT N5KDV EM41”, highlighted in red. Results will be similar to those in the previous step, except the Tx frequency (red marker) is not moved. Such messages are usually in response to your own CQ, or from a tail-ender, and you probably want your Tx frequency to stay where it was.

By holding down the Ctrl key when double-clicking on a decoded line you can cause both Tx and Rx frequencies to be moved. This behavior can also be forced by checking Lock Tx=Rx.

Double-click on the message from KF4RWA in either window. He is sending “73” to K1JT, signifying that the QSO is over. Most likely you want to send 73 to him, so the message “KF4RWA K1JT 73” is automatically generated and selected for your next transmission. (Alternatively, you might choose to send a free text message or to call CQ again.)

Click somewhere on the waterfall to set Rx frequency (green marker on waterfall scale).

Ctrl-click on the waterfall to set both Rx and Tx frequencies.

Double-click on a signal in the waterfall to set Rx frequency and start a narrow-band decode there. Decoded text will appear in the right window only.

Ctrl-double-click on a signal to set both Rx and Tx frequencies and decode at the new frequency.

Click Erase to clear the right window.

Double-click Erase to clear both text windows.

Select JT9+JT65 on the Mode menu.

Toggle the Tx mode button to read Tx JT65, and set the Tx and Rx frequencies to 1718 Hz.

Double-click on Erase to clear both text windows.

Set Bins/Pixel = 7

Adjust the width of the Wide Graph window so that the upper frequency limit is approximately 4000 Hz.

Select File | Open and navigate to ...\save\samples\130610_2343.wav. The waterfall should look like this:

Confirm that mouse-click behavior is similar to that described earlier, in Example 1. WSJT-X automatically determines the mode of each JT9 or JT65 message.

Double-click on the waterfall near 815 Hz: a JT65 message originating from W7VP will be decoded and appear in the Rx Frequency window. Between the UTC and Freq columns on the decoded text line you will find dB, the measured signal-to-noise ratio, and DT, the signal’s time offset in seconds relative to your computer clock.

Double-click on the waterfall at 3196 Hz. The program will decode a JT9 message from IZ0MIT:

Scroll back in the Band Activity window and double-click on the message CQ DL7ACA JO40. The program will set Tx mode to JT65 and Tx and Rx frequencies to that of DL7ACA, 975 Hz. If you had checked Double-click on call sets Tx Enable on the Setup menu, the program would configure itself to start a QSO with DL7ACA.

Double-click on the decoded JT65 message CQ TA4A KM37. The program will set Tx mode to JT9 and the Rx and Tx frequencies to 3567 Hz. The program is now configured properly for a JT9 QSO with TA4A.

Select File | Open and navigate to ...\save\samples\130418_1742.wav.

To enable automatic band-hopping, check the Band Hopping box on the main window.

Click Schedule to open the WSPR Band Hopping window, and select the bands you wish to use at each time of day.

Band-switching occurs after each 2-minute interval. Preferred bands are identified with time slots in a repeating 20-minute cycle, according to the following table:

If the preferred band is not active according to your band-hopping schedule, a band will be selected at random from among the active bands.

If the box labeled Tune is checked for a particular band, WSJT-X transmits an unmodulated carrier for several seconds just after switching to that band and before the normal Rx or Tx period starts. This feature can be used to activate an automatic antenna tuner (ATU) to tune a multi-band antenna to the newly selected band.

Depending on your station and antenna setup, band changes might require other switching besides retuning your radio. To make this possible in an automated way, whenever WSJT-X executes a successful band-change command to a CAT-controlled radio, it looks for a file named user_hardware.bat, user_hardware.cmd, user_hardware.exe, or user_hardware in the working directory. If one of these is found, WSJT-X tries to execute the command

user_hardware nnn

In the above command nnn is the band-designation wavelength in meters. You will need to write your own program, script, or batch file to do the necessary switching at your station.

To activate the VHF-and-up features check the box labeled Enable VHF/UHF/Microwave features on the Settings | General tab.

If you will be doing EME, check the box Decode at t = 52 s to allow for the EME path delay on received signals.

If you will use automatic Doppler tracking, check the box Allow Tx frequency changes while transmitting. On the Radio tab select Split Operation (use either Rig or Fake It: you might need to experiment with both).

The main window reconfigures itself as necessary to include controls supporting features of each mode. For example, in JT4 mode the central part of the main window will look like this:

On the View menu, select Astronomical data to display a window with important information for tracking the Moon and performing automatic Doppler control. Check the box labeled Doppler tracking to ensure that the right-hand portion of the window is visible.

Select Full Doppler to DX Grid if you know your QSO partner’s locator and he/she will not be using any Doppler control.

Select Constant frequency on Moon to correct for your own (one-way) Doppler shift to or from the Moon. If your QSO partner does the same thing, both stations will have the required Doppler compensation. Moreover, anyone else using this option will hear both of you without the need for manual frequency changes. The hypothetical “man in the moon” will copy all of you on the selected nominal frequency.

In the example depicted above, the moon-based nominal frequency is 100 kHz above the stated band edge, or 10368.100 MHz for the 10 GHz band. The home station two-way self Doppler shift is +6193 Hz, so the one-way shift is +3096.5 Hz. Therefore, the receive frequency is set to 10,360.103097 Hz. When a transmission is started, the frequency is reset to 3096.5 Hz below the nominal frequency.

Spinner controls at top right of the Astronomical Data window let you set a working frequency above the nominal band edge. The frequency above band edge is the sum of the numbers in these two controls (kHz + Hz).

Select JT4 from the Mode menu.

Select the desired submode, which determines the tone spacing. Higher spacings are used on the higher microwave bands, to allow for larger Doppler spreads. For example, JT4F is generally used for EME on the 10 GHz band.

If using a transverter, set the appropriate offset on the Settings | Frequencies tab. Offset is defined as (desired transceiver dial reading) minus (desired on-the-air frequency). For example, when using a 144 MHz radio at 10368 MHz, Offset (MHz) = (144 - 10368) = -10224.000. If the band is already in the table, you can edit the offset by double clicking on the offset field itself. Otherwise a new band can be added by right clicking in the table and selecting Insert.

The JT4 decoder in WSJT-X includes optional facilities for averaging over successive transmissions and also correlation decoding, sometimes known as “Deep Search”.

By convention, EME with JT4 can use “short form” messages. To activate automatic generation of these messages, check the box labeled Sh on the main window.

Select Echo from the Mode menu.

On the Astronomical Data window check Doppler tracking and Constant frequency on the Moon

Choose your desired test frequency using the Frequency above nominal band edge controls.

Be sure that your rig control has been set up for Split Operation (either Rig of Fake It) on the Settings | Radio tab.

Click Enable Tx on the main window to start a sequence of 6-second cycles.

WSJT-X calculates and compensates for Doppler shift automatically. Your return echo should always appear at the center of the plot area on the Echo Graph window, as in the screen shot below.

Your callsign and grid locator set to correct values

PTT and CAT control (if used) properly configured and tested

Computer clock properly synchronized to UTC within ±1 s

Radio set to USB (upper sideband) mode

Radio filters centered and set to widest available passband (up to 5 kHz).

Bins/Pixel controls the displayed frequency resolution. Set this value to 1 for the highest possible resolution, or to higher numbers to compress the spectral display. Normal operation with a convenient window size works well at 2 to 8 bins per pixel.

JT65 nnnn JT9 sets the dividing point (blue marker) for wide-band decoding of JT65 and JT9 signals in JT9+JT65 mode. The decoder looks for JT65 signals everywhere, but JT9 signals only above this frequency.

Start nnn Hz sets the low-frequency starting point of the waterfall frequency scale.

N Avg is the number of successive FFTs to be averaged before updating the spectral display. Values around 5 are suitable for normal JT9 and JT65 operation. Adjust N Avg to make the waterfall move faster or slower, as desired.

A dropdown list below the Palette label lets you select from a wide range of waterfall color palettes.

Click Adjust to activate a window that allows you to create a user-defined palette.

Check Flatten if you want WSJT-X to compensate for a sloping or uneven response across the received passband. For this feature to work properly, you should restrict the range of displayed frequencies so that only the active part of the spectrum is shown.

Select Current or Cumulative for the spectrum displayed in the bottom one-third of the Wide Graph window. Current is the average spectrum over the most recent N Avg FFT calculations. Cumulative is the average spectrum since the start of the present UTC minute. Linear Avg is useful in JT4 mode, especially when short-form messages are used.

Four sliders control reference levels and scaling for waterfall colors and the spectrum plot. Values around midscale are usually about right, depending on the input signal level, the chosen palette, and your own preferences.

Smoothing is active only when Linear Average has been selected. Smoothing the displayed spectrum over more than one bin can enhance your ability to detect weak EME signals with Doppler spread more than a few Hz.

Log QSO raises a dialog window pre-filled with known information about a QSO you have nearly completed. You can edit or add to this information before clicking OK to log the QSO. If you check Prompt me to log QSO on the Setup menu, the program will raise the confirmation screen automatically when you send a message containing 73.

Stop will terminate normal data acquisition in case you want to freeze the waterfall or open and explore a previously recorded audio file.

Monitor restarts normal receive operation. This button is highlighted in green when the WSJT-X is receiving. If you are using CAT control, toggling Monitor OFF relinquishes control of the rig; if Monitor returns to last used frequency is selected on the Settings | General tab, toggling Monitor back ON will return to the original frequency.

Erase clears the right-hand decoded text window. Double-clicking Erase clears both text windows.

Decode tells the program to repeat the decoding procedure at the Rx frequency (green marker on waterfall scale), using the most recently completed sequence of received data.

Enable Tx toggles the program into automatic T/R sequencing mode and highlights the button in red. A transmission will start at the beginning of the selected (odd or even) sequence, or immediately if appropriate. A transmission will not be started any later than 24 s into a UTC minute.

Halt Tx terminates a transmission in progress and disables automatic T/R sequencing.

Tune may be used to switch into Tx mode and generate an unmodulated carrier at the specified Tx frequency (red marker on waterfall scale). This process may be useful for adjusting an antenna tuner. The button is highlighted in red while Tune is active. Toggle the button a second time or click Halt Tx to terminate the Tune process.

A drop-down list of frequencies and bands at upper left lets you select the operating band and sets dial frequency to a value taken from the Frequencies tab on the Settings window. If CAT control is active the radio’s dial frequency will be set accordingly; if not, you must tune the radio manually.

Alternatively, you can enter a frequency (in MHz) or band name in recognized ADIF format, for example 630m, 20m, or 70cm. The band-name format works only if a working frequency has been set up on that band, in which case the first working frequency on that band is selected.

If you are using CAT control, a small colored circle appears in green if the CAT control is activated and functional. The green circle contains the character S if the rig is detected to be in Split mode. The circle becomes red if you have requested CAT control but communication with the radio has been lost.

If DX Grid contains a valid Maidenhead locator, the corresponding great-circle azimuth and distance from your location are displayed.

The program can maintain a database of callsigns and locators for future reference. Click Add to insert the present call and locator in the database; click Lookup to retrieve the locator for a previously stored call. This feature is mainly useful for situations in which the number of active stations is modest and reasonably stable, such as EME (Earth-Moon-Earth) communication.

Check Tx even to transmit in even-numbered UTC minutes. Uncheck this box to transmit in the odd minutes. This selection is made automatically when you double-click on a decoded text line, as described in the Basic Operating Tutorial.

The Tx and Rx audio frequencies are usually set automatically by double-clicking on decoded text or a signal in the waterfall. They can also be adjusted with spinner controls.

You can force Tx frequency to the current Rx frequency by clicking the Tx<Rx button, and vice-versa for Rx<Tx. Check the box Lock Tx=Rx to make the frequencies always track one another. The on-the-air frequency of your lowest JT9 or JT65 tone is the sum of dial frequency and audio Tx frequency.

The Report control lets you change a signal report that has been inserted automatically. Most reports will fall in the range –26 to +10 dB. Remember that JT65 reports saturate at an upper limit of -1 dB.

Select the next message to be transmitted (at the start of your next Tx sequence) by clicking on the circle under Next.

To change to a specified Tx message immediately during a transmission, click on a rectangular button under the Now label. Changing a Tx message in mid-stream will slightly reduce the chance of a correct decode, but it is usually OK if done in the first 10-15 s of a transmission.

All six Tx message fields are editable. You can modify an automatically generated message or enter a desired message, keeping in mind the limits on message content. See Protocol Specifications for details.

Click on the pull-down arrow for message #5 to select one of the pre-stored messages entered on the Settings | Tx Macros tab. Pressing Enter on a modified message #5 automatically adds that message to the stored macros.

Clicking a button puts the appropriate message in the Gen Msg box. If you are already transmitting, the Tx message is changed immediately.

You can enter and transmit anything (up to 13 characters, including spaces) in the Free Msg box.

Click on the pull-down arrow in the Free Msg box to select a pre-stored macro. Pressing Enter on a modified message here automatically adds that message to the table of stored macros.

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