JS8Call is a digital mode based on FT8, allowing for messaging with very weak signals. Whilst FT8 is a “QSO-only” protocol where only locations and signal reports are exchanged, JS8Call allows for arbitrary text-based messages to be exchanged.
Does my radio support JS8Call?
Many radios support JS8Call “out of the box”, such as my Yaesu FT-710 and my ICOM IC-705, however some radios require an additional interface such as the DigiRig to add this capability. For example, I use a DigiRig Mobile with my Yaesu FT-857D to add digital capability.
Setting up your Radio
I will be releasing tutorials that cover the specific configuration of the radios that I have access to (Yaesu FT-710, ICOM FT-710, and the Yaesu FT-857D with a DigiRig Mobile), however the general steps are similar for many radios.
Connect the Radio to your PC and configure the COM port. On my FT-710 this involves using a USB-A to USC-B cable (commonly called a “printer cable” these days) whereas with my IC-705 it requires a USB-A to USB-micro cable. As this will be communicating with the radio it’s best to use a high quality and short cable, and it’s likely a good idea to add a couple of ferrites to the cable, especially if you experience lockups whilst transmitting.
You may need to install drivers for your radio, for example ICOM offers drivers for the IC-705 here and Yaesu offers drivers for the FT-710 here. Once you’ve installed the drivers, you radio should show in Device Manager under “Ports (COM & LPT)”, for example my ICOM IC-705 shows up as two devices “IC-705 Serial Port A (CI-V)” and “IC-705 Serial Port B”, each with a COM ports number, for me that’s COM5 and COM6 respectively, but yours will likely be different. I have JS8Call to use COM5.
Configure JS8Call to Connect to the Radio. This will involve telling JS8Call about the settings that your radio requires for its communications, most likely this will involve setting at least the COM port to use and a Baud Rate. For some radios this is configurable, such as on my FT-710 this is found under Func > Operation Settings > CAT-1 Rate, and the default is 38400. Whereas on the IC-705 there is no setting on the device, and I’m told it will automatically adjust to what it receives – but I also have this set to 38400. For all of my radios, I have the PTT method set to CAT and the mode set to USB. For split operation I have it set to “Rig”.
Getting Started with JS8Call
The main configuration steps needed for JS8Call are to set your callsign and grid location, under File > Settings > General > Station. Personally I also have Heartbeats enabled under Mode > Enable Heartbeat Networking.
Whilst it’s possible to check that everything is working with the connection to your radio by enabling “Tune” and seeing the tune tone on your radio’s waterfall, or similar, heartbeats allow you to check that other stations can actually hear you. If you hit HB on the left of the middle row of buttons (you have to Enable Heartbeat Networking first, as stated above, for this button to show) then your radio will transmit for 15 seconds, then receive for 15 seconds and you should get signal reports from other stations.
Here you can see that I have received a signal report. I sent this with my ICOM IC-705 with about 5 watts and got an SNR of +6 which is a good strong signal. Generally anything higher than -18 is likely workable, anything below -23 will be very difficult.
At this point, I have configured my radio, I’ve checked my signal is getting our with a heartbeat. I can now start making CQ calls with the CQ or I can respond to other stations call by right clicking their message and selecting either a saved message, or direct message. It’s common to start a QSO with a signal report (“HW CPY?” will request this, where as Direct message > “send a signal report to the selected callsign” will reply to a SNR request). Then you can simply start typing messages in the box labelled “Type your outgoing message to <callsign> here”. However you should remember that messages are restricted to 13 characters, and sending a longer message will take multiple transmission windows. Whilst this is completely fine, it may take a long time to transmit (15 seconds per 13 character block). It’s also a good idea to end your message with “BTU” for “Back to you” so the other station knows you have finished your transmission and it is their turn to respond.
What’s the point of JS8Call?
FT8 and the related protocol JS8Call both offer one major benefit, extremely weak signal propagation. Whether you’re operating on low power, in a noisy environment, or with a compromised antenna, FT8 can get your signal out there. However, it’s a “QSO only” protocol and stations expect to exchange locations and signal reports only, and then move on.
This is very useful for people who are working on project such as trying to reach the furthest station they can or trying to contact all countries within Europe. As well as people doing POTA activations. As all you may care about is making contact.
However, if you’re looking for a more conversational experience, JS8Call is likely what you’re looking for. It offers the weak signal benefits of FT8 although allows you to exchange text-based messages, so you can go further than a signal report and exchange information about stations, your situation, or whatever you want.