XLAPRS Old Hardware

This page documents the 1st revision of the hardware I used to run XLAPRS while mobile during 2002. I am working on a new computer to reduce power usage and size; see the 'new hardware' link to the right for details

The main piece is a 12v-powered Linux PC which currently sits in a cardboard box in the back of my Toyota 4runner. It is connected to a Garmin GPS III+ and a Kantronics KPC-3+ TNC. The LCD display is a 240x64 graphical model from Matrix Orbital. It's mounted above the rear-view mirror in a place which Toyota engineers expected me to put a garage door opener. Input is via a custom-built controller that interfaces to the 5x5 matrix keypad controller on the LCD display.

Main computer pics

The computer is an AOpen micro-ATX PC motherboard with an AMD Athlon 1.1Ghz CPU. 128MB RAM, built-in video, ether, 2x serial ports. It boots a stripped-down RedHat 7.2 Linux with a 2.5 kernel from a 256MB compactflash card (no hard drive), using a CF-IDE adapter from PC Engines. The entire Linux install uses less than 40MB of the card, including SSH, shells, my software, and tons of libraries. For additional serial ports I mounted a Comtrol RocketPort 8J card (RJ-11 connectors) on a PCI right-angle riser card. The power supply is a KP-DX250H, 12v in, ATX power out. Power consumption is approximately 7A at 12v, which is a weebit high for my tastes -- that's what I get for using an AMD CPU. This means I can only run for 1-2 hours with the vehicle's engine off.

The micro-ATX board is mounted to standard PC-case standoffs epoxied to a piece of lucite. Underneath the lucite is the Kantronics KPC-3 TNC. All serial port connectors are RJ-11s; simple wiring but no hardware flow control. I am temporarily using a Kenwood TM-D7 radio for access to the 144.39Mhz APRS channel.

Overhead view of the comp-in-a-box.

Side view of the comp-in-a-box

Detail view of the comp-in-a-box. You can see the plug-in CF-IDE adaptor and how the multiport serial card is mounted on the riser to keep height down.

LCD/Keypad Install pics

Coming soon