M0IAX

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JS8Call an overview for new users

Posted: 26 Apr 2021 10:15 AM PDT
https://m0iax.com/2021/04/26/js8call...r-new-users-2/



Introduction




JS8Call has been in around for a few years now, but its sadly still not
very popular. Many Amateur Radio Operators around the world are using the
WSJT-X software constantly to make contacts comprising of a simple signal
report exchange and that’s fine, but its not for everybody. If you have
tried FT8 you will already know of its great weak signal capabilities
allowing DX Contacts when conditions are difficult. So what if you could
use a mode that has similar properties to FT8 but also allow a keyboard to
keyboard communications as well as integration to allow messages and
location reports to be sent into the APRS network? Well, in a nutshell
that’s what JS8Call does.




Back in March of 2018 I managed to get involved in the testing of some new
software for Amateur Radio. I joined a very small team of Operators who
were mainly in the USA but also three in Europe, including myself. This
software was called FT8Call, the original name of what is now called
JS8Call.




As you may have already deduced from the original name of the software it’s
a new digital mode that is built upon the popular weak signal digital mode
FT8. If uses the same modulation as FT8 allowing it to be decoded at -24Db,
and it also uses the same 15 second timer to send out its messages.




It is there that the similarities end though, because unlike FT8’s simple
Signal Report exchange format, JS8Call allows free text
keyboard-to-keyboard communications.




Recent updates to JS8Call added 3 new speed modes for JS8Call and
integration to APRS that means if you send an APRS message using JS8Call a
receiving station with an internet connection will forward that to the APRS
network. More about that later.




Hardware Requirements




You don’t need the latest high-powered computer to run it. It will run as
Happily on the Raspberry Pi as it does on the latest high-end laptop.
Supported operating systems include various distros of Linux, Windows 10
and MacOS X (the standard MacOS installer will also run on the new apple
silicone). That said there are also many operators in the pre-release test
that are running it on older operating systems such as Windows XP and
Windows 7.




Like any other computer based digital mode you also need some way of
connecting the computer to the radio via a sound card interface of some
kind. On my PC and Icom IC-7300 this is done with one USB Cable for CAT
Control and the Sound Interface provided in the Radio. With the
introduction of radios with Wifi such as the Icom IC705 (my favourite
radio) you can connect the computer completely wirelessly to the radio
which removes the need for another wire which is great news especially in
the field.




Installation




Installation on the supported operating systems is a simple case of
downloading and running the installer package. You can find the latest
installation packages on the JS8Call website by following the download link
at the top of the page https://js8call.com




User Interface




The user interface is laid out well and does also work quite well on a
touch screen interface as well as with a mouse. The main window is split
into the Band Activity pane (showing messages you have decoded).








Incoming Message Activity Pane, Call Activity pane (showing the list of
callsigns you have heard), the Message box (here you will enter your
outgoing messages) and the Waterfall at the bottom giving you a visual
indication of where the signals are in the passband – you can also select
the frequency offset you want to use here. The six buttons top right
display settings in use and you can click them to enable/disable or bring
up a menu of options (also available in the Menus top left)




Using JS8Call




So lets get down to actually using the software. If you have already
installed and used WSJT-X then JS8Call should work right away, if no you
will need to make sure your connection from computer to your radio is
correctly set up. There are some guides on my website to get you started
(link at end of this article). Once installed there are a couple of things
you need to set up. First enter your callsign on the General/Station
settings page. Then entry your Maidenhead Grid locator and customise your
Station messages, and finally set up your radio interface and select the
sound card to use.








Back in the Main User interface calling CQ is as simple as clicking on the
CQ button, JS8Call will put your CQ message in the message window and send
it at the start of the next 15 second time frame. Once you receive a reply
you can click on the station’s callsign in the Call activity pane and then
type your message into the message box and click send, JS8Call will
automatically add your callsign and the selected station’s callsign to the
message and send it.




You have the option to use 4 different tx speeds (you can receive and
decode all no matter which is selected) the speeds and their properties are
(details taken from the JS8Call Documentation)



Slow 30 second frames 25Hz bandwidth and around 8WPM decoded down to
-28dBNormal 15 second frames 50Hz bandwidth and around 16WPM decoded
down to -24dBFast 10 second frames 80Hz bandwidth and around 24WPM
decoded down to -20dBTurbo 6 second frames 160Hz bandwidth and around
40WPM decoded down to -18dB




Hint: I tend to call CQ using Normal mode and then switch to a faster speed
once I see what the reported SNR is between myself and the far station. If
trying for DX select slow mode to call CQ and then switch once contact is
established (if possible) I have had some quite lengthy QSOs using slow
mode. Great results but you need to be patient




That’s all there is to it. There is some automation like the ability to set
it up for your station to reply to directed commands/messages automatically
but the actual QSOs are comtrolled by the operator with free text or the
use of Saved messages which can be pre-defined by the user. There is also a
“Heartbeat� function that will send out your callsign and grid locator at
user-defined intervals. This is not a CQ call but a mechanism that lets
others know your station is on the air and they can call you direct, or
maybe send your station a relay command to pass a message to someone that
they cannot hear.




APRS




You can use JS8Call to send messages and locations into the APRS network
and view on APRS.fi. By formatting your outgoing message correctly you can
send emails, APRS messages, SMS messages (if supported in your country),
position reports and even spot yourself for SOTA. Ive written a python app
with user interface that you can use to do this, but all it does if format
the text correctly. It uses the JS8Call API to send the text.








The Power of Low Power




The great thing about this mode is that it can be decoded at -28dB. Which
means that you don’t need to run your radio at full power to chat with a DX
station. During the recent QSO party weekend I was able to set my IC-7300
at minimum power (0% which gave an output power of approx. 350mW) and have
a conversation with Julian OH8STN in Finland over 1300miles away. I was
also getting acknowledgments to my “Heartbeat� from stations in North
America during the evening.




What’s the Cost?




JS8Call costs nothing, it’s based on open source software and although
parts of JS8Call contain code that Jordan KN4CRD owns the copyright to he
has assured us that he will never charge for the software.




Conclusion




JS8Call has come on in leaps and bounds since I joined the test team back
in may. And its evolved into what’s going to be a great mode for
communication over long distances using relatively low power. Jordan has
done some fantastic work and is very supportive of new users on the
groups.io groups and is happy to accept requests for improvements and new
functionality. He’s doing Amateur Radio a great service and I can’t thank
him enough for that.




If you haven’t yet tried JS8Call then consider giving it a go, there are a
lot of users out there who are happy to help you get up and running, and
there are a few facebook groups you can join and of course the JS8Call
website contains links to all the documentation. You can always give me a
shout and I will be happy to help!








Links









My website and softwa




https://m0iax.com





https://m0iax.com/download-files





https://github.com/m0iax





JS8Call website




http://JS8Call.com





Download JS8Call and Documentation




files.js8call.com/latest.html