Yet Another APRS Client

An apt title for this post, but also for the software in question. Yet Another APRS Client (YAAC from now on) is a new program written by Andrew, KA2DDO that has recently entered beta test status. I stumbled across it a few days ago and am now running it on my G4ILO-2 VHF iGate.

YAAC map display with US Geological Survey topographic data.)

YAAC is written in Java so it runs equally well on Windows, Mac and Linux platforms as long as you have a recent Java runtime installed.

YAAC is open source software and uses open source mapping (Open Street Map – OSM). APRSISCE does too, but whereas it uses bitmap tiles, YAAC uses vector-based map data. This makes the maps look a bit different (more as if they were drawn by a spider.) You can easily add topographical data from the US Geological Survey (the screenshot above shows this.) YAAC also supports the use of scanned-in maps but I haven’t tried this.

YAAC is very easy to use. There is a wizard to help you set up the program, though there is also an expert mode that allows you to get to all the settings directly. There are far fewer things that can be changed than APRSIS32 has which is one reason it is easier to use, but YAAC’s user interface is more standard. A File menu is on the left of the menu bar, Help on the right, and all the configuration settings are on a multi-tabbed dialog box not nested in three levels of menus. YAAC would be an ideal program for someone new to APRS, which is not to belittle the program in any way as it does all the things that most users would be perfectly happy with.

YAAC supports a wide range of TNCs including TNC2 compatibles and the Kenwood mobiles. In APRS mode the Kenwood D700/D710 can only be used receive-only. In Packet mode the Kenwood can be used as a KISS TNC. Believe it or not I hadn’t realized it had this capability until Andrew pointed it out to me. Just two commands (KISS ON, RESTART) are needed to put the Kenwood into KISS mode. The other thing that confounded me for quite a while is that the Kenwood TNC expects hardware flow control. Once that setting had been made everything started to run perfectly.

YAAC’s “Radio View”

One disadvantage of using the Kenwood D700/D710 in Packet mode is that the rig’s display doesn’t show any APRS information.However, Andrew has implemented a rather neat “radio view” which emulates the Kenwood display. The only extra thing that would make the emulation complete would be to limit it to only those packets received over the radio. With an APRS feed covering a wide area the display changes too quickly to be readable.

YAAC doesn’t provide as much information about APRS objects as APRSISCE does.The window on the right is what you get when you click on one of the G4ILO icons. When two or more stations are co-located the calls overwrite one another making them unreadable. APRSISCE manages to position the calls so they don’t overlap at all.

Because YAAC uses vector graphics it does a better job of displaying APRS icons and even orients the icons of moving objects in the direction of motion. Zoom in to street level and you’ll discover that icons are provided for points of interest. I was quite impressed when I saw what was displayed for our small town of Cockermouth. I think these objects come from OSM data.

Street-level display of Cockermouth including places of interest

You might get the impression that I really like this new APRS client. It appears to be well designed, well written and is well supported by Andrew, its developer. It’s a very impressive piece of software. I originally intended just to try it out for a couple of days but I think I’ll stick with it for the time being.

Julian Moss, G4ILO, is a regular contributor to and writes from Cumbria, England. Contact him at [email protected].

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