Sunday, June 30, 2013

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.

Wednesday, June 26, 2013

Milestone at the end of the road

My Motorola Milestone 2 smartphone, which I bought nearly two years ago, has gone kaput. When I slide out the keyboard, the display goes blank. The device is usable, but only as an ordinary phone. I can imagine what has happened. There is probably a flexible ribbon cable like in the KX3 connecting the two halves, and a trace has broken. (A good job I've got the charger for the KX3 so I don't have to keep opening it up to change the batteries.)

Of course, it is out of warranty. The question is, is it repairable at a reasonable cost? Motorola's support site won't give an estimated cost of repair. "Send it to us and we'll give you a quote" they say. I'd really like a ballpark figure for what it is going to cost before doing that.

I guess I'll just have to spring for a new phone. But there weren't many alternatives with a real hardware keyboard and I expect there are even fewer now. I wish I could type using the software keyboard (which I'll have to for now) but I have a 50% error rate. I don't think my fingers are much fatter than normal. How do you guys manage? Perhaps you don't text much and don't do email on the phone.

Another Android APRS client

Good news for APRS enthusiasts with Android devices. Lynn Deffenbaugh, KJ4ERJ, is embarking on a port of his popular and successful APRSISCE to the Android platform, called APRSISDR.

I use the words "embarking on" advisedly. Although there is a Yahoo group and a collection of testers (including yours truly) the software is in an embryo stage at the moment. You can see the beginnings of an APRS client starting to form but Lynn is really just testing the Android platform at the moment to see how various key things can be accomplished. I would hazard a guess that it will take several months before something usable appears, though those who were in at the start of APRSISCE development will recall that it advanced in leaps and bounds. It's going to be a fun ride, but for most I think it will be best to wait patiently for more news to emerge. Watch this space!

Monday, June 24, 2013

An Aaargh! moment

Some of you may have received an invitation to join my LinkedIn network from me today. To those who accepted, thank you. To those who found the invitation unwelcome, I apologize.

It was not my intention to spam you in any way. Unfortunately I didn't look carefully enough at what was displayed so that instead of emailing just those whom I had painstakingly selected from the list, the invitations went to all of the hundreds of addresses in my Gmail contacts list.

It was a real Aargh! moment, but by the time I had uttered the exclamation it was too late! Judging by all the invitations I have received in the past from people I don't remember, I don't think I am the first person to have done this.

Saturday, June 22, 2013

FUNcube Dongle

I've been spending a few hours playing around with a FUNcube Dongle Pro. There was a lot of excitement about this project a couple of years ago when it started. In order to get one you had to be quick off the mark on Ebay. I never succeeded, then I got ill and then I forgot about it. This one was passed on to me by a friend who successfully purchased one but never used it.


I started off by following the instructions in the user manual. I followed this by installing and setting up a complicated-looking SDR program called Spectravue. I was baffled by most of this program's settings and I wasn't sure if it worked.

What I should have done was try some of the SDR programs I installed when I was playing about with USB TV dongles at the beginning of the year. I started SDR#, selected the FUNcube Dongle from a pull-down list, clicked Start and it just worked!


Simon Brown's SDR-Radio worked as well, and with equal ease, though as luck would have it I tried it on the very day that the (free) licence key for the program expired. This appeared to come as much of a surprise to Simon as everyone else. As I type, Simon has just uploaded a fix which I have yet to install.

I thought I would try using the FCD as an ADS-B receiver which I did with the TV dongles but I soon discovered that I can't. The FCD looks like a budget USB sound card to the SDR software, so its bandwidth is restricted to 2 x 48kHz. The digital TV dongles can transfer a much wider bandwidth. This is noticeable if you try to receive Band 2 FM radio - through the FCD the signal sounds distorted on peaks because the bandwidth isn't quite wide enough for FM stereo which needs a full 100kHz..

It will be interesting to use the dongle with the FUNcube 1 satellite when it gets off the ground later this year (we hope!) In the meantime I'll use it to watch for Sporadic-E in the VHF band.