K7NAV - Craig

[spatialminds]

Hey everyone... Up until last Sunday I drove a 99 Land Rover Discovery II with a lot more mods than my wife wanted me to add. I'm still pondering what rig to build next.

In my spare time I run NorthwestOverlandSociety.org which is an expedition style offroading website for people in the PNW. I enjoy any sort of 4x4 trail, the high mountains, shrub steppe, high desert, and just about any other ecosystem. Our group uses HAM exclusively when on the trail.

I've been a HAM for a couple of years. I have an Icom 2720h w/ a Tiny Tracker 4 setup for APRS and a Kenwood D710a also setup for APRS. I use both radios with my software, Overland Navigator, for displaying APRS info on a topo map while offroading. I mostly use 2m on the trail, and haven't spent a lot of time exploring HAM beyond Vx and APRS. Still getting into it.

http://spatialminds.com/images/DII_HawkinsMtn.jpg

[KC0NNT]

Welcome! Beautiful picture.

[spatialminds]

Thanks. It's one of my favorite sets of trails.

A little more info on my HAM setup since that's the theme of this forum.

Power: Wired direct to dual optimas under the hood with inline fuses on both the positive and negative terminals.

http://www.4x4ham.com/attachment.php?attachmentid=301&d=1278543293

Radio: Icom 2720h is mounted under the driver seat. The faceplate and mic are mounted forward of the transfercase shifter.

http://www.4x4ham.com/attachment.php?attachmentid=307&d=1278543297

Speaker: An external speaker was added to the A pillar, hidden under a factory tweeter cover.

http://www.4x4ham.com/attachment.php?attachmentid=305&d=1278543296

Antenna: I had it on top of my roofrack, but after whacking it on one too many trees (I live in the forested PNW) I gave up and mounted it on spare tire carrier that is on the back door. It worked much better than I expected, and performance degradation was much less than I expected.

It is just barely low enough to clear my rooftop tent when it is open.

http://www.4x4ham.com/attachment.php?attachmentid=303&d=1278543295

Computer: My offroad navigation system is based around an EO Tuftab semi-ruggedized and sunlight visible 7" touchscreen Ultra Mobile PC (UMPC). Despite the photo, the sight lines aren't obscured at all when driving. I leaned way over onto the armrest with the camera when taking this photo.

http://www.4x4ham.com/attachment.php?attachmentid=302&d=1278543294


Computer Mount: I used a RAM 1" ball mount system to mount the UMPC to the top of the dash.

http://www.4x4ham.com/attachment.php?attachmentid=304&d=1278543295

GPS: I use a MightGPS weatherproof GPS. It requires the roof to be drilled, but makes for a very factory looking installation. The GPS itself has the SIRF III GPS chipset inside so it is very sensitive. The UMPC has bluetooth, so I'll probably replace the wiring with a bluetooth connection. The goal is to have a single wire (power) being the only thing going to the UMPC on the dash.

http://www.4x4ham.com/attachment.php?attachmentid=299&d=1278543291

TNC/Tracker: TinyTrack IV tracker. GPS plugs into the computer, and a second cable goes from the computer to the Tiny Tracker GPS input cable. To the TT4 the computer *is* the GPS. I'm going to experiment around with a Serial to Bluetooth adapter to make the connection from the computer to the tracker.


http://spatialminds.com/images/APRS_Passthrough.jpg

Note: The TT4 allows an alternate configuration where a GPS plugs into the TT4, and the TT4 outputs that data to it's PC interface cable (the computer). This allows the GPS NMEA and the APRS NMEA to occupy the same connection, and allows the TT4 to beacon even if the computer is turned off. This only works with the TT4. The scenario described above also works with a Kenwood D7xx, the trackers from Argent Data Systems, etc.

Software: Overland Navigator for both offroad USGS Topographic Navigation and for APRS display. This is my company's software.

Some of the features include:

Seamless USGS Topo maps
GPS Tracks and waypoint recording and display
APRS specific NMEA support
Location specific Sunrise / Sunset times
UTM or Lat/Lon Coordinate Display
Continuous GPS Track Storage to Disk


http://www.4x4ham.com/attachment.php?attachmentid=300&d=1278543292

http://www.4x4ham.com/attachment.php?attachmentid=306&d=1278543297


On the APRS side it supports the extended NMEA sentences that the Kenwood D7xx radios, Tiny Tracker 4, Argent Data Systems, etc trackers output so it can show the correct APRS symbol.

http://spatialminds.com/images/aprs1.png

In contrast to most handheld GPS units, when new stations are heard, Overland Navigator will update the location on the map instead of adding an additional waypoint.

The APRS waypoints automatically fade away and then expire on their own. This lets me visually see how long it's been since I last heard from an APRS station. If I have the interval set to 40 minutes, and a symbol is just about ready to disappear then you know it's been about 40 minutes since you last heard from it.

http://spatialminds.com/images/APRS_Fadeout.jpg

The APRS symbols to have a consistent look/feel to contrast with the background maps, and to be distinguishable from regular Overland Navigator waypoints (square).

Primary Symbols
http://spatialminds.com/images/aprs_primary.jpg

Secondary Symbols
http://spatialminds.com/images/aprs_secondary.jpghttp://www.4x4ham.com/images/misc/pencil.png

[K7VZ]

Killer!!!

.....

[KC0NNT]

Wow! Nice post!
I love that stuff.

[spatialminds]

Thanks for the kind words. Considering how to fit a similar setup into a TJ now. Hmmm....

[K7VZ]

I will happily let you prototype on my XJ!

[spatialminds]

I will happily let you prototype on my XJ!

If you are looking for ideas, I have quite a few customers from NAXJA.org running Overland Navigator. I haven't seen anyone post any install photos, but if you ask someone might post some.

Craig

[spatialminds]

If anyone is interested, there's a two page review of Overland Navigator in the summer 2010 issue of Overland Journal. Unfortunately, they reviewed the previous version that didn't include APRS display.

Overland Navigator is designed with the offroader in mind. While we have a lot of our own ideas going forward, if anyone has any feature suggestions please send me a message. I'm always interested in hearing from people.

[K7DCL]

Thanks for a great writeup, well done.