Holux GM-270 CF GPS
by Holux
 - October 2002 -
 

Intro and where to buy

The Holux CF GPS is one of the more anticipated CF GPS receivers as it is the first one to use a SiRF IIe/LP chipset. This chipset brings increased sensitivity and battery life. More on this later.
A big thank you to Tony who provided me with this personal receiver, thanks!

It is not currently available for purchase outside of Taiwan. According to Frank, product manager with Holux in Taiwan, deals are being worked out to bring it to the US and to Europe at a price comparable receivers. Considering that there are currently no other CF GPS receivers with a SiRF IIe/LP chipset I'm not sure what that will be. I'll post updates here as they become available.
Apparently the Holux CF GPS is currently being sold in Taiwan with the an external antenna and the MapKing/PaPaGO navigation software for about $150, which is a great price. Semsons is now carrying it for $180....Very good value in regards to the performance.

Specs:

From Holux's site: specs 
PDF also available here: .pdf


Size and Appearance: 

This CF GPS is a Compact Flash Type 1 receiver and is more compact than most CF receivers out there.
In the following pictures it is shown side by side with the Bluetooth GPS and the Billionton CF GPS.

These pictures (pardon the dust on the screen, it's due to the darn flash ;-)) show that the Holux CF GPS is slightly thicker than the ultra thin Billionton receiver but is actually a little bit shorter. It will still stick out quite a bit from your CF slot though.
 

Battery Life and Power Supply:  

See the "Battery Life" page for details

Like all current CF GPS solutions (except for the NeoGPS) it doesn't have its own power supply and will use the one of the PocketPC it is connected to. See the "Battery Life" page for what consequences this has. My tests found that thanks to the use of the SiRF IIe/LP chipset, the Holux CF GPS  required far less power than the other CF GPS receivers, and now even the  old generation of PPC's like the iPaq 36xx can be used fairly comfortably, especially if you turn off the backlight.

You can also activate the Trickle mode with GPS Information (see below), but due to the way trickle mode works, this is not recommended for difficult reception conditions.
Still, I thought I would measure the impact on battery life but realized that the GPS didn't seem to register the commands to set itself in trickle mode. I used the Holux utility to start with and being unsuccessful I brought out the big guns and fired up u-Center (by u-Blox) using the Bluetooth GPS to validate the way I was sending the commands. I'm sorry to report that trickle mode can't be activated on the Holux GPS I tested. I'm following up with Holux to see if there's something else I can try. Again, having seen the way that mode degrades the performance of the  Bluetooth GPS, it's far from being a deal breaker, still it would be nice to get it to work as advertised ;-)

Operation:

I found the Holux CF GPS to be very easy to operate. It does not require any specific drivers on your PocketPC (at least if you're running PPC2002) so all you need to do is drop it in the CF slot of your PDA or of the expansion sleeve of your PDA. It can also be used with a laptop if need be, using Windows  drivers provided by Holux.

While I didn' have any problems using my PCMCIA sleeve, I did find that using the Memplug Dual CF sleeve, in some cases, it took several attempts/soft resets for the card to be recognized by the 3670 or 3975. Couldn't really determine a pattern but it seems from a message I got at one point that it does draw quite a bit of power to get started and that the PPC might not have been ready to provide it. I didn't experience that problem with the Billionton, PocketMap or Transplant CF GPS receivers.  Holux is aware of the problem has but has not yet decided whether they would implement a fix or not. I hope they do because if you want to use a CF GPS with an iPaq and large maps that's the cheapest option.

Settings:

Like all the GPS receivers using the SiRF chip, it can easily be set to any combination of baud rates and protocol. All you need is Leadtek's excellent CE Monitor linked at the top of the "software" webpage. In addition Holux provides, GPS Information (looks like an update of the old GPS Info utility provided with the Pretec units), a small utility that lets you activate WAAS or the trickle mode.

1) Baudrate:
Factory default is set at 4,800bps but can be easily modified to 9,600/19,200/38,200/57,600bps with CE Monitor
This will guarantee compatibility with all open navigation programs (i.e. all navigation programs except Travroute's CoPilot)

2) Output Protocol or language:
You can easily switch back and forth between NMEA and SiRF with CE Monitor.
Switching to SiRF is a must for all Destinator aficionados...

3) WAAS
Although it's bit of a buzzword these days for GPS receivers, WAAS  isn't really needed for road navigation, where the software generally uses a "snap to road" trick instead.
For off-road use though it can be useful for people who need a very accurate position. However, depending on where you're located it might in fact degrade the quality of the position calculated by the GPS.
The good news is that Holux has activated it by default and give you the option to turn it on and off at no extra charge with a small utility. In comparison Teletype will let you do that on their CF GPS receiver but only if you buy their utility for $160...

 

Satellite Reception and Time to acquire a fix

See this page for detailed timings and comparisons

Thanks to the use of the very sensitive SiRF IIe/LP chipset, the Holux CF GPS got a fix very quickly most of the time as shown in the table linked above.
Once it had a fix, even though I moved it around quite a bit in my car and even put my PPC on the passenger seat a few times, it never lost the fix.
For my testing I didn't feel the need to use the included external antenna, unlike for the Billionton CF GPS where it solved some problems due to difficult satellite  environments. The antenna could help though in very difficult conditions (urban canyons, etc...) so it's nice to have one handy.

Compatibility with mapping/routing software:

In my limited testing, I've found the Holux CF GPS to operate perfectly with all the programs I tried.
- Destinator (make sure you use switch to SiRF mode)
- Pharos Ostia - NMEA/4,800bps
- Mapopolis -NMEA /4,800bps
- TomTom Route Planner USA - NMEA
- TomTom GPS plug-in (used by CityMaps, TomTom Online and TomTom Navigator). Using the NMEA mode because for some reason in SiRF mode TomTom (still not fixed in 1.41 but Navigator still works ok) wasn't reading the position properly. Unlike the current version of Destinator however, TomTom GPS works fine in NMEA mode.
- There are others out there, but they should all work provided you can select COM ports easily, except those that are locked to a receiver like Travroute's CoPilot or Distefora's mobile navigator.

Conclusion:

Revisions:

10/31/02 - Made note about WAAS being activated by default
               - Made note about Trickle mode settings not being registered by the GPS
11/05/02 - Added note about MemPlug incomatiblity
                - Added US availability