“The idea with JS8Call is to take the robustness of FT8 mode and layer on a messaging and network protocol for weak signal communication on HF with a keyboard-to-keyboard interface. JS8Call is heavily inspired by WSJT-X, Fldigi, and FSQCall and would not exist without the hard work and dedication of the many developers in the amateur radio community.”

Guides and tutorials

We’ve put together some quick guides and tutorials on JS8Call operating and best practice. Can’t see what you need? contact us and we will do our best to help!

Quick reference guides for JS8Call

How do I call CQ?
Just click on the CQ button. JS8Call will put a CQ message in the message pane, you can type in more text if you want. (NOTE You don’t need to enter your callsign, JS8Call will do that for you before the message is sent).

Then Click Send (The send button will show you how many frames it will send)

How do I reply to a CQ Call?
There are a few options here, in this section we will cover the “REPLY” one found in the menu.

So you’ve spotted a station calling CQ and want to reply? Great, communicating is what JS8Call is all about! Right Click on the callsign either on the Activity pane, or the heard stations pane which will select the callsign (the row will turn blue) then select the “Directed to <CALLSIGN>” option (where <CALLSIGN> will be replaced by whatever one you picked).

Now click the “REPLY” menu option, what happens next is that JS8Call Will look in your settings and get the text you put in the Reply Message text box, this is HW CPY? by default but you can change it to anything you want. Remember, you don’t need to enter your callsign – JS8Call will add this for you. If you want to add some more to the reply go ahead and enter it now, once you are done hit the send button.

Thats it, your message is on the way!



What is the AUTO button for?
JS8Call allows users to send commands to other stations, for example if you want to get a signal report from a station in your hear list you would right click on that station, select the Directed to <CALLSIGN> menu option, then select “? – What is my signal report?” and JS8Call will sent the signal report query to the station eg


if OH8STN has auto enabled his FT8Call will send back the signal report


So if you want to respond to commands from other stations then enable AUTO, or disable it to prevent your station replying.

Whats is the BEACON button for?
BEACON enables the Beacon. This sends out a beacon message at a time interval which is configurable in settings. The purpose of the Beacon is to let other operators know you are there even if you are not actively calling CQ or already in a QSO, if stations have AUTO enabled they will reply to your beacon with an SNR message.

Whats that "lightning bolt" ⌁ at the end of the message?
This is a special character, its called an ala . It is a symbol to indicate the End of Transmission, the last frame of the message has been transmitted with nothing else to follow. This means you get a visual indicator that the transmission is done and you can begin transmitting a reply.

What are Directed Messages?
There are special directed messages that you can send to stations to have them automatically reply if they have AUTO enabled. They are comprised in the form of [CALLSIGN][COMMAND].


M0IAX? – request signal report from M0IAX

KN4CRD$ – request KN4CRD to tell you what stations he can hear (replies with the top 4 ranked by SNR)

OH8SHN!73 THANKS FOR THE QSO – displays the message in a message box in OH8STN’s FT8Call window


Available commands:


  • ? – What is my SNR?
  • @ – What is your QTH (station location)?
  • & – What is your QTC (station message)?
  • % – What is your station power?
  • $ – What stations are you hearing? (Will transmit the top 4 ranked by SNR)
  • QSO [CALLSIGN]? – Can you communicate directly with CALLSIGN?
    • If the station ACKs, they will send back the SNR and the last time the callsign was heard at their station
  • |message – Please ACK and retransmit the following message
    • The message is retransmitted by the receiving station  verbatim with the addition of “DE [CALLSIGN]” added to the end of the message…meaning you do not need to add it to your message.
  • !message – Please display this message in a alert dialog and ACK if acknowledged
  • #message – Please ACK if you receive this message in its entirety
  • AGN? – Have the station automatically retransmit their last message
  • QTC – Send station message
  • QTH – Send location message
  • GRID – Send a long-form grid locator (to be spotted on a map via PSKReporter & APRS-IS)
  • QSL? – Did you receive my last transmission?
  • QSL – I received your last transmission
  • YES – I confirm your last inquiry
  • NO – I negative confirm your last inquiry
  • HW CPY? – How do you copy?
  • RR – Roger. Received. I copy.
  • FB – Fine Business
  • 73 – I send my Best Regards / End of Contact

You can also type any of these commands into the message box directly once you know them.

What is ALLCALL for?
ALLCALL allows you to send one of the directed messages to anyone listening. If they have AUTO enabled their station will automatically act on the command you sent.

For example, lets say you’ve been listening for a while and you are waiting to chat to your buddy but his callsign hasn’t appeared in your heard list. Here you can right click on ALLCALL select Directed to ALLCALL->BEACON REQ [CALLSIGN]?.

once selected the text will be put in the message pane, now just replace the highlighted text ([CALLSIGN]) with your buddy’s callsign



Now click send

Once the message has sent, if you are being heard and stations have AUTO enabled stations who have KN4CRD in their heard list will reply to you, you could then send a relay message through any one of them!

Some options in the menu are disabled as they are not relevant to ALLCALL, so try right clicking on one of those stations that sent you a reply and send them a message or use the relay to send to your buddy.

Can I change the order of the Stations in my JS8Call heard list?

Yes you can, simply right click on a station (or all call) in the list and select an option in the sort by list:

Installation Guides

How do I install JS8Call on my Mac?

Firstly download the installation package from the download link.

Once downloaded open a finder window and go to where the file was downloaded to (Usually “Downloads”)

Double Click on this file and it will open the terms and conditions. Click Agree to continue

This will open a finder view of the installation package

If you have not installed JS8Call or WSJT-X before you will need configure some shared memory, if you have installed and successfully run either application you can skip this step. (Please read the ReadMe.txt file for ,more info – this is just a quick start guide)

First Drag the file named sysctl.conf from the installation package window to your Mac Desktop

Next you will need to open a terminal window and enter some commands

To do this, open Launchpad and in the find box type terminal and press enter.


now you need to enter the commands that are in the ReadMe file. Enter them exactly or it won’t work correctly.

sudo cp $HOME/Desktop/sysctl.conf /etc/

sudo chmod 664 /etc/sysctl.conf

sudo chown root:wheel /etc/sysctl.conf

Now you need to restart your Mac for the changes to take effect.

Once you have restarted then open a terminal window and enter

sysctl -a | grep sysv.shm

shmmax 14680064, if not then please refer to the ReadMe.

Now all that’s left to do is to Open the insallation package again and drag the JS8Call icon to your Applications folder

This will copy the app to your Mac and you will be able to find it in your Applications Directory in finder.




Video Tutorials

How To send you location to the APRS Network
One of the great new features of JS8Call is the ability to send messages to the APRS network. For most messages you need to know the correct way to format the message, sending your position is built into JS8Call and is very easy to do, Julian shows us how in this tutorial video on the official JS8Call youtube channel.

How to Download the JS8Call software

Simple, just click the button to go to the downloads page!