A new CLI utility and daemon for JS8Call!

Hello all, I wrote a new utility for JS8Call. It can be found at https://github.com/ThreeSixes/js8cli. JS8CLI has been in the works and moving slowly for the last couple months. This new utility replaces the some of the functionality of the JS8CallTools GUI with command line functionality and can run as a daemon in the background. I also added a few features to this that probably should already be in JS8Call such as automatic GPS location support and the ability to update APRS position information via JS8Call automatically and periodically. This utility also allows you to send SMS messages via APRS from the console over JS8Call.

JS8Call sending a text message driven by js8cli being run in a command line window.
Screenshot of the CLI utility feeding JS8Call

This utility leverages JS8Call’s API and can run in either TCP or UDP mode. I also wrote a Python 3 class that can be used to interface with JS8Call’s API which isn’t really documented though it’s fairly simple to use (see mainwindow.cpp). It’s mostly just JSON sentences sent over a network stream to the application.

The JS8CLI application is also a good citizen and leverages GPSD to share the GPS with other applications rather than bogarting the serial port. This also makes it possible to get position information from another host on a network. This could be useful in fixed or networked applications or cases where a GPS needs to be remote. The SMS functionality doesn’t require GPS capabilities at all.

Cold weather backpack setup test

So, the weather in Portland has been pretty snowy which is a touch unusual! As most folks have been inside and not out attempting to drive on icy and snowy roads which are not plowed I decided I’d take my HT for a walk in the cold weather and test methods of keeping it warm enough to not have the battery fail as the temperature is dropping to ~18F with wind chill. My partner and I have been walking to the grocery store and taking our dog out so I decided to test an external antenna I’d built to mount on my backpack a year ago in the gnarly weather. I did some tests with APRS and some 5w FM phone as well. The theory here is that keeping the HT inside the fairly sealed bag would preserve some amount of air that’s warmer than the bag’s surroundings. It seemed to work as I was out with this setup for a few hours at a time and battery performance was within expectations.

Snow and ice covered backpack set on a snow-covered sidewalk with counterpoise extending down and antenna extending up.
Setup covered in ice and snow.

In order to not go stir crazy I’ve been taking walks with my partner and we’re close enough to a grocery store to just walk and pack our food in our bags which is very fortunate. I’ve taken the opportunity to test different ways of carrying the HT so it doesn’t get too cold, and to test a MOLLE antenna holder with a simple antenna and counterpoise setup. During the grocery store run pictured below I was able to reach stations in SE and NE Portland with a strong signal. I was between 2 and 9 S units into a station in Battelground, WA as well depending on structures around me. The antenna I’m using in this picture is a Nagoya NA-771. I used that instead of my Signal Stick because the signal stick doesn’t stay rigid in cold temperatures and will curve and lay over giving poorer performance. The speaker mic was used as both a speaker that I could hear outside the bag and as a sacrificial component in the event something gets too wet. A $30 speaker mic is much cheaper than a new HT. I did test the SWR on this setup and 2m performed very well near 1.2, but 70cm performance was poor with the SWR being near 2.8.

The small bit of orange paracord is used to secure the speaker mic for cable routing purposes. When the mic comes un-clipped intentionally or on accident this cord makes it easier to grab and replace or remove and use. The longer orange paracord holds the weight of the HT in side the bag so the antenna cable and speaker mic don’t hold it up. It’s also necessary to hold it up in the bag to make sure there’s enough speaker mic cable to reach outside the bag and to my shoulder.

HT in the bag suspended by paracord.

The HT holder inside the bag is suspended by the longer bit of paracord that runs through a loop on the HT holder. This suspension system also makes it easy to load the bottom of the bag with heavier items that might otherwise crush the HT or damage connectors.

The above gallery shows the antenna assembly set up but not mounted to the webbing on the backpack.