                    Notes on WSJT-X Installation for Mac OS X

                    -----------------------------------------



If you have already downloaded a previous version of WSJT-X then I suggest 

you change the name in the Applications folder from WSJT-X to WSJT-X_previous 

before proceeding.  



I recommend that you follow the installation instructions especially if you

are moving from v2.5 to v2.6 or later, of WSJT-X or you have upgraded macOS.



Double-click on the wsjtx-...-Darwin.dmg file you have downloaded from the main web-site.

Make sure that you leave this window open for the remaining installation steps.



Now open a Terminal window by going to Applications->Utilities and clicking on Terminal.



Along with this ReadMe file there is a file:   com.wsjtx.sysctl.plist  which must be copied to a

system area by typing these lines in the Terminal window and then pressing the Return key after

each line.



      sudo  cp  /Volumes/WSJT-X/com.wsjtx.sysctl.plist  /Library/LaunchDaemons

      sudo  chown root:wheel  /Library/LaunchDaemons/com.wsjtx.sysctl.plist



you will be asked for your normal password because authorisation is needed to copy this file.

(Your password will not be echoed but press the Return key when completed.)



If your Mac is using Sonoma 14.6 or later then in addition to these two commands you must visit:

    

      System Settings > General > Login Items > sysctl    and select ON for sysctl.



IMPORTANT: Now re-boot your Mac otherwise these changes will not take effect. 



After the reboot you should re-open the Terminal window as before and you can check 

that the change has been made by typing:



      sysctl -a | grep sysv.shm



If shmmax is not shown as 52428800 then contact me since WSJT-X will fail to load with

an error message: "Unable to create shared memory segment".  If the value of shmmax

is shown as 20971520 then it is probable that you have download JTDX.   WSJT-X and JTDX

cannot both control the shmmax parameter.  Contact me for advice.



You can now close the Terminal window.  It will not be necessary to repeat this procedure 

again, even when you download an updated version of WSJT-X.  It might be necessary if you

upgrade macOS.

 

Drag the WSJT-X app to your preferred location, such as Applications, and close the window.



You need to configure your sound card.   Visit Applications > Utilities > Audio MIDI 

Setup and select your sound card and then set Format to be "48000Hz 2ch-16bit" for 

input and output.  On rare occasions problems with audio output to your rig can be

corrected if you select 44100Hz for output format.



Now double-click on the WSJT-X app and two windows will appear.  Select Preferences 

under the WSJT-X Menu and fill in various station details on the General panel.   

I recommend checking the 4 boxes under the Display heading and the first 4 boxes under 

the Behaviour heading.



Depending on your macOS you might see a pop-up window suggesting that wsjtx wants to use the

microphone.   What this means is that audio input must be allowed.  Agree.



Next visit the Audio panel and select the Audio Codec you use to communicate between 

WSJT-X and your rig.   There are so many audio interfaces available that it is not 

possible to give detailed advice on selection.  If you have difficulties contact me.   

Note the location of the Save Directory.  Decoded wave forms are located here.



Look at the Reporting panel.  If you check the "Prompt me" box, a logging panel will appear 

at the end of the QSO.  Visit Section 11 of the User Guide for information about log files

and how to access them.



Finally, visit the Radio panel.  WSJT-X is most effective when operated with CAT 

control.  You will need to install the relevant Mac device driver for your rig, 

and then re-launch WSJT-X. Return to the Radio panel in Preferences and in 

the "Serial port" panel select your driver from the list that is presented. 



You may need a device driver for your Mac. The USB/UART Bridge chip inside the Icom,

Yaesu and Kenwood radios is a Silicon Labs USB to UART Bridge Controller and the Mac

drivers are available here:



https://www.silabs.com/products/development-tools/software/usb-to-uart-bridge-vcp-drivers



Visit the SiLabs site and download v6 for a Mac. Then in WSJT-X if you use the drop-down menu

for Serial Port you should see something like /dev/tty.SLAB_USBtoUART if the driver has been

installed correctly.  Make sure you read the release notes that come with the driver.



WSJT-X needs the Mac clock to be accurate.  Visit System Preferences > Date & Time 

and make sure that Date and Time are set automatically.  The drop-down menu will 

normally offer you several time servers to choose from.



On the Help menu, have a look at the new Online User's Guide for operational hints 

and tips and possible solutions to any problem you might have.



Please email me if you have problems.



--- John G4KLA     (g4kla@rmnjmn.co.uk)



Addendum:  Information about com.wsjtx.sysctl.plist and multiple instances of WSJT-X.



WSJT-X makes use of a block of memory which is shared between different parts of

the code.  The normal allocation of shared memory on a Mac is insufficient and this 

has to be increased.  The com.wsjtx.sysctl.plist file is used for this purpose.  You can 

use a Mac editor to examine the file.  (Do not use another editor - the file 

would probably be corrupted.)



It is possible to run two instances of WSJT-X simultaneously.  See "Section 16.2 

Frequently asked Questions" in the User Guide.  If you wish to run more than two instances

simultaneously, the shmall parameter in the com.wsjtx.sysctl.plist file needs to be modified as follows.



The shmall parameter determines the amount of shared memory which is allocated in 4096 byte pages

with 50MB (52428800) required for each instance.   The shmall parameter is calculated as: 

(n * 52428800)/4096  where 'n' is the number of instances required to run simultaneously.

Replace your new version of this file in /Library/LaunchDaemons and remember to reboot your

Mac afterwards.



Note that the shmmax parameter remains unchanged.  This is the maximum amount of shared memory that

any one instance is allowed to request from the total shared memory allocation and should not

be changed.



If two instances of WSJT-X are running, it is likely that you might need additional

audio devices, from two rigs for example.  Visit Audio MIDI Setup and create an Aggregate Device

which will allow you to specify more than one interface.  I recommend you consult Apple's guide

on combining multiple audio interfaces which is at https://support.apple.com/en-us/HT202000.  



2.  Preventing WSJT-X from being put into 'sleep' mode (App Nap).



In normal circumstances an application which has not been directly accessed for a while can be

subject to App Nap which means it is suspended until such time as its windows are accessed.  If

you find that WSJT-X seems disabled check this by opening Applications > Utilities > Activity Monitor and

then select Energy and look at the column marked App Nap.  If you see wsjtx marked "Yes" then you need

to disable App Nap by opening a Terminal window and typing:

    defaults  write  NSGlobalDomain  NSAppSleepDisabled  -bool  YES

This will disable App Nap for all applications.  If you wish to reverse this type:

    defaults delete  NSGlobalDomain  NSAppSleepDisabled

