Panasonic Toughbook CF-28

I only bother with MK3's at the moment. I have 4 CF-28's, all fully maxed out. The CF-28 has proven to be most popular due to having more space inside to add interesting hardware. The "RIM Daughterboards" provide a serial communications interface that can be used to interface very interesting additions. In addition to GPS modules, what else can you think of that uses a serial port?

CF-28 Service (Repair) Manual

This manual is invaluable in understanding your CF-28.


If you are the sort that likes to do hardware modifications, the schematics and block diagrams have proven useful.



If you happen to have purchased a unit on ebay that has the cmos password set, it's easy to solve. Just open the bottom panel and disconnect the cmos battery, then without a power adapter or main battery installed, turn the power switch on for a moment. That should clear the issue. I've used this method a dozen times.

CF-28 Mini-PCI

(click on image)

You should remove the factory ethernet and the factory modem, and install a 3COM Combo card, which will give you a free mini-pci slot to use for a modern wifi card (if you are not using the built-in pcmcia slot for wifi (I insist on using them). Some people do this in order to use the internal PCMCIA card for bluetooth. I don't need bluetooth so I'm fine with using a Cisco 350 or 340 (LC-35x, or LC-340) and installing a new wifi antenna on the LCD lid. Some day I may use a mini-pci wifi card but fabricate a new antenna lead that uses the lid-mounted antenna.


There are (3) pcmcia sockets, but only two are seen, hence you will often hear of the "hidden" pcmcia socket. You have to remove the ethernet/modem coverplate to get to the "hidden" socket. This is where the "built-in" Cisco wifi card goes. I'll upload some images of this area soon.

CF-28 Hard Drive

The CF-28 uses a unique, ruggedized hard drive caddy to encase the drive in a protective gel glove, usually with a heater strip to make sure the drive is not too cold to safely function. The caddy is easy to disassemble but it's important that you put it back together correctly so make sure you pay attention to detail. When I have the opportunity to take some pictures of this, I'll add more here.


CF-28 Battery Care

Battery health is important. Make sure you refresh your battery(s) at least once a month. Here is a screenshot of a battery refresh operation. (click on image)


CF-28 Factory GPS

I recommend using OziExplorer with the built-in GPS. You can download the USGS topological maps (DRGs) and use them directly within OziExplorer. The GPS installed in the CF-28 is only 8 channels which means it's not as nice as the modern units available but you can't beat the integrated gps, it works very well.

Many people have complaints that it is slow to lock up, well if you experience this, make sure you replace the battery backup installed on the GPS-sled and you'll notice it locks up PDQ. The problem most people don't seem to understand is that if that battery is dead the GPS has to re-initialize each time it is turned on.

I use both OziExplorer and iGuidance. It depends if I'm in the desert or the city :)




Here is a short document reviewing IGuidance with the CF-28 I wrote in 2008…


SHTF power for your Toughbook

Get a DC-DC converter (12vdc input) and any sort of 12v battery you can basically get power from a portable panel, a car battery, anything that provides something close to 12vdc. This is an example of how to keep your Toughbook going even where there is no commercial power.

RIM Antenna to WIFI Conversion


CF-28 Dock (LEDCO)

I installed a few of these in my vehicles. I grok them fully now. I have taken them apart, enhanced them, hacked interesting things into them.

Here are a few pictures to look at until I can get some actual text added on what I've done, what I know about them and why I think they are cool.

Installing after-market GPS module on RIM daughterboard

EM-408 GPS Engine

Chipset SiRF StarⅢ
Frequency L1, 1575.42 MHz
C/A code 1.023 MHz chip rate
Channels 20 channel all-in-view tracking
Sensitivity -159 dBm
Position 10 meters, 2D RMS
5 meters, 2D RMS, WAAS enabled
Velocity 0.1 m/s
Time 1us synchronized to GPS time
Default WGS-84
Acquisition Time
Reacquisition 0.1 sec., average
Hot start 1 sec., average
Warm start 38 sec., average
Cold start 42 sec., average
Dynamic Conditions
Altitude 18,000 meters (60,000 feet) max
Velocity 515 meters /second (1000 knots) max
Acceleration Less than 4g
Jerk 20m/sec **3
Main power input 3.3V DC input
Power consumption 75mA (Continuous mode)
Dimension 36.4mm * 35.4mm * 8.3mm
Baud rate 4,800 to 57,600 bps adjustable
Electrical level TTL level, Output voltage level: 0V ~ 2.85V
Output message SiRF binary or
Operating Temp -40℃ to +85℃

Here are some useful images, when I have more time I will add the pertinent technical details and attribute credit where credit is due.

EM-408 Manual


Replacing Standard CD with DVD Writer