Thursday, September 03, 2009

IGate issues

Ever since I was a child, I have been fascinated by maps. My attempt to receive signals from satellites led to my finding out more about Automatic Packet Reporting System (APRS) and I became interested in trying its position tracking capabilites, as well as the potential it offers for ham radio-based text messaging. So I'm currently awaiting the arrival (hopefully today) of a Yaesu FT-8R APRS-capable HT in my shack.

While I was waiting I decided to set up an APRS Internet Gateway or IGate, so that my position when I'm out and about with the VX-8R can be monitored on sites like findu.com, aprs.fi and OpenAPRS. This wasn't something I wanted to tie up the Elecraft K3 and DB6NT transverter doing, so I set up my FT-817ND to act as my APRS receiver, using my computer's integrated sound card (I have a separate SB Live 24 card for use with the K3.) For the IGate antenna, I reinstalled in the attic my 2m Slim Jim. However, last night while making some PSK31 contacts on 80m with the K3 I noticed that my IMD Meter was showing a poor signal again.

For some reason that I do not understand, having the Slim Jim connected to my station upsets the K3 and makes it produce a distorted signal. At the time, I put it down to having too many antennas in not enough space and I took the Slim Jim down. But now I need it. Disconnecting the Slim Jim from the FT-817 cures the bad signal from the K3, as does disconnecting the FT-817 from the shack power supply. It was a short step from this to finding that operating the FT-817 from its own independent power supply rather than the Diamond GSV-3000 that also powers the K3 leaves the signal clean. At least, it does on 80m. I haven't tested on any other bands yet. Unfortunately the only other power supply I have that's suitable is a small switcher, so now I have a clean PSK31 signal but warbly noises wandering around the HF bands.

The other problem related to the IGate that I haven't yet solved is what software to use for it. Like most newcomers to APRS (I guess) I started off with UI-View32. This is quite a nice program that displays APRS position reports on a map, offers APRS messaging capability and also has a built-in IGate. However, it is no longer being developed or supported as its author is a silent key. Also I preferred a standalone IGate that I could leave running all the time without the overhead of position tracking on a map.

The only alternative I could find is AGWUIDigi, from the same author as the AGW Packet Engine that I use. I think this works, but it appears not to post its own position beacons to the Internet, so when I run it my IGate does not appear on any of the maps. This is a significant limitation to me, as I want my station to be shown so that others can see that there is APRS activity in my area, and hopefully encourage more use of this interesting mode. Perhaps it's a simple configuration issue, but I can't see it.

3 comments:

Anonymous said...

Greetings! I just set up AGWUiDIGI here as well and seem to have found the same limitation with regard to it's posting it's own position to the internet.

Right now I am running a one-way fill-in iGate to post locally heard traffic to the iGate, but I'm not showing up. Oh well. Work is underway to put up a full node, but if this is a simple misconfiguration then we've both made the same mistake. :)

g4ilo said...

I didn't get an answer about this on the AGW Yahoo Group either.

The state of software for APRS on Windows seems pretty dire. Ui-View32 seems the most popular program but it has some issues with APRS messaging which will never be fixed as no-one has taken over development following the death of its author.

Xastir seems to work the best as a gateway/node, but to use that you need to run Linux (or follow some incredibly complicated instructions that are well beyond me to run it under Cygwin on Windows.)

Rex said...

What about digiplex? anyone use that effectively with AGWPE? I know it is also a node etc... but on the old data it has APRS capability although not sure it has been updated in some time either?

WD0AJG