Holux M-241 GPS logger with LCD display - reviewed

Summary

The Holux M-241 GPS logger (available from Amazon.com in the USA) has a similar cylinder form to some other loggers, but adds a new feature: an LCD display which can show current location and GPS time, as well as enabling the changing of settings on the device itself.

It takes a single AA battery, and although it can run off of USB power, it can't recharge the battery.  It uses the 32 channel (51 channel) MTK chipset.  It comes with very basic photo geocoding software for inserting photos into Google Earth tracks, the software is Windows-only.  It has Bluetooth serial support, so it can work with compatible devices (e.g. mobile phones, laptops, PDAs) as a Bluetooth GPS.  The device itself is also Mac compatible, using BT747 software, including track download over Bluetooth.  130,000 log points with user-settable time interval or distance trigger.

See my GPS logger comparison spreadsheet for a full feature comparison with other loggers.

If you want to be able to check your location in real-time or change settings on the fly, this may be the logger for you.  However the Windows software is very basic, and I found some minor sensitivity issues.  As well, it does not automatically start logging as soon it gets a satellite fix (you have to watch and manually start it once it has a signal).  You may find some of the other models I have reviewed better suited to your needs.

Note: Although you may see mention of a Holux GR-241, there is no such device.  It may have been an early model number for the M-241.

Details

My colleague Chris actually noticed the design is reminiscent of a film canister.  There is a small plastic cylinder on top through which you can thread the provided thin string that attaches to a strap.

Here's what it looks like, compared to some other loggers, it's the one in the centre

You can see that in colour (orange), size and shape, it's almost identical to the GiSTEQ DPL700 PhotoTrackr Lite.  They are strikingly similar models, even down to the GPS chipset (MTK), with the M-241 LCD display being the main differentiator in terms of hardware.

Here's the packaging and what comes in it

It includes a USB cable, a strap, a battery, a car adapter for power, and a 7-day license for smart2go mobile (cellphone) map software (which works only on Windows Mobile 5 and some Nokia phones, unfortunately).  You can get an optional and rather oddly-named "travel adapter" which is just a wall-socket USB power cable.

Using the LCD display, you can control logging settings (time interval or minimum distance).  You can also see a count of remaining log record storage (continuously decremented if the log is running) - a very nice feature so that you know exactly how much memory you have left.  As well, for the first time with a GPS logger, I actually can find out where I am in real-time, since it has a lat/long display.  GPS time is also displayed (you have the option to adjust the time display for you timezone).  This time display will make it very easy to keep your camera synchronized with the GPS.

It also has a sort of "odometer" mode, where you can measure distance travelled.

Surprisingly, despite the elaborate controls and display, I could find no way to set a waypoint (perhaps because it considers every track record location a "waypoint").

The included Windows software (Holux Logger Utility) is quite basic (as is common for most loggers other than the GiSTEQs).

Once you have the serial driver installed, you can connect to the device

The logger settings can also be controlled from software

"Upload" brings up a small dialog box

Files will have the device name ("user name") you have chosen prepended.

"Combine JPEG file" is one option for photo processing.  It will "combine" matching photos into the Google Earth .kml

"Write Total Track Log" means one file combining all the tracks, in addition to all the individual logs.

The software will save both a Holux datafile (.trl tracklog filename) and a Google Earth .kml file, with start, end, and every intermediate datapoint included as a waypoint.  Here's an example of me walking to work from my bus.  Waypoints are in yellow, with date/timestamps in white, the track runs through the middle of the image.

and here's the .kml file itself

Download Richard_M-241_Start_20080117-094618_Finish_20080117-100317.kml

It does not produce time-based .kml

There are various other output formats available

The software has no concept of true photo geocoding with EXIF stamping, instead it will only create KML tracks with embedded photos.

It will let you make time adjustments to sync your photos with the GPS time of the track points

[Here's where I wrote about photos and the software, and TypePad ate it, so let's try again.]

The matching worked fine, I did some photos from my K790a camera, offset by -5 (my timezone).

However, all the photos are embedded in the .KML in the same section as the "waypoints" (the track log points), distinguished only by a camera icon.  If you have dozens or more photos, you will have a heck of a mess trying to sort them out from the yellow track points.

Photo icons manually selected (purple with white date stamps)

Default appearance with everything selected.  Good luck trying to find your photos.

Just to emphasize, there is no way to select just your photos all in one click, you have to manually scroll through the waypoints directory and select them one by one.

The waypoints directory showing one photo

Photos are not auto-rotated in the Google Earth display.

Here's what a single photo looks like (it's a snow groomer, in case you're wondering)

Please note: this is not true photo geocoding, the GPS coordinates are not embedded in the photos (I checked the processed images with IrfanView using the EXIF extension - no changes to the EXIF or IPTC).   The photos are actually completely untouched and unaltered as far as I can tell.

To do true photo geocoding, you will have to convert your .trl files to a standard format (e.g. GPX) and use some other software (not provided by Holux) to embed the locations into the photo EXIF.

The M-241 will also work on Windows and Mac using the BT747 software, see my posting "BT747 support for Holux M-241 on Mac over USB and Bluetooth" for more information.

I tested the Holux M-241 against various other loggers:

M-241 with 5s logging interval, BT-Q1000 with 10s logging interval, not sure of HGE-100 (TrekBuddy recording interval), AGL3080 always fixed 1s interval (1Hz), Sony GPS-CS1 always fixed 15s interval

20080117 - roughly the same as the Qstarz BT-Q1000 and Sony HGE-100

20080119 - this is a problematic set of tracks from skiing at Vorlage - the M-241 overall does well, but there are a few tracks (the ones I am certain are wrong marked with "X") where it is clearly not correct (fortunately for my health, I didn't suddenly start skiing through the woods).  M-241 (cyan track) and BT-Q1000 (orange) both in ski jacket pockets.  This may be an antenna issue, the Holux does have a "this end up" indication, and I can't guarantee what direction that was pointing as it tumbled around in my pocket.

The original Holux .kml is quite large, so I have saved .kmz out of Google Earth.

Holux-Vorlage-20080119.kmz

Qstarz-Vorlage-20080119.kmz

20080123: roughly the same, keeping in mind the different logging intervals, except for the Sony GPS-CS1 (green) which not surprisingly is a bit more off-track given its SIRFstarII chipset

Download Holux-M241-20080123-part-1.kmz

Download Holux-M241-20080123-part-2.kmz

Download Ottawa-20080123-Qstarz.kmz

Download Ottawa-20080123-Sony.kmz

Download Ottawa-20080123-AGL3080.kmz

20080126: Back at Vorlage.  Again an anomalous track (big loop at top).  Could be due to battery I suppose, the Holux battery died part-way through the day.    Cyan is Holux again, Orange is Qstarz again, Red is AMOD AGL3080.

Here are two of the tracks.  There is more in the Qstarz because the Holux battery died (the advantage of having a 32-hour rechargable battery in the Qstarz).

Download Voralge-Holux-M241-20080126.kmz (just noticed filename typo, sorry)

Download Vorlage-20080126-Qstarz.kmz

These are just my observations in terms of the GPS performance, I don't have the equipment or software to do extensive sensor tests - I hope someone will do some detailed testing about the impact of the orientation of the M-241 and the antenna sensitivity.

UPDATE 2008-02-11: I did some additional testing and I got good tracks as long as the M-241 stayed with the antenna pointing upwards.  ENDUPDATE

Things that could be improved:

• no way to have it auto-start logging when a satellite fix is obtained
• no way to set a waypoint (UPDATE 2008-02-11: May be possible in Lat/Long display mode.)
• awkward battery door (common problem with this type of design)

Comments

[midtoad]

thanks for the review. I just received my M-241 today and fired it up for a bike ride home from work. However I didn't recall that you need to manually start the logging (unlike my Wintec WBT-201) so I guess it didn't record anything. I'll try again tomorrow.

I'm not impressed with every point being recorded as a waypoint, though that should be easy to fix with a Python script that reads a .gpx file and writes out another one with each waypoint converted to a trackpoint.

[Eric]

Have you attempted to change the logging resolution using any of the other MTK tools? I know that some of them support 5Hz logging, http://www.gpspassion.com/forumsen/topic.asp?TOPIC_ID=81990. This is something I'd be very interested in finding out about prior to buying...

Thanks!

[Richard Akerman]

Eric, I tried setting the M-241 to log at 5Hz (5 data points per second) using BT747, but I wasn't successful.

It continued to record only one data point every five seconds.

[René]

I've not got a M-241 yet since one thing concerns me a bit (though I don't know in practice if it's a problem) - but in the online PDF manual I found (p. 12) that, the device should be "stopped" before you turn it off since the log can be damaged... Ahmm I thought then what happens, when the battery is dead - is the log then also damaged or does the device stop automatically by itself?? - so the log is saved ok?

Thanks for a great review ;)

[Robert Wong]

The M-241 looks really interesting. From reading your reviews, it has a lot of features (display!!, bluetooth). I wish it had the vibration sensor (like the GISTEQ DPL700 PhotoTrackr Lite). I also wish it (like you said) the "automatically start logging upon turn on".
RWW

[Dick]

I've found that pressing the mode button when in the Lat/Long display mode stores waypoints. Don't know why it's not documented though.

[Oliver]

I am interested in the M-241, too. But i would like to use it with my mobile phone to navigate. But in the discription is written that the GPS-mouse mode is USB only? Is that true or didn´t I get it right? I need it to navigate over bluetooth.

Thanks
Oliver

[Richard Akerman]

The M241 provides a full real-time NMEA location stream over Bluetooth.

I will clarify the information in my blog. (Often GPS mouse mode
refers only to tethered, over USB, rather than Bluetooth.)

[Knut]

Thanks for a superb intro to the Holux M-241 which have almost all the features I need. However, I need to have the bluetooth and logging features on at the same time. Is this possible?.
Knowing that in a car or plane I can view my position in, say Map Point, and when done I can take only the M-241 with me and download to the Google Earth would be nice. Any other GPS gadget that can accomplish this if the M-286 can't?

[Richard Akerman]

The M-241 can do simultaneous Bluetooth and logging.

[Michal]

Richard,
Many thank for the great review! You were wondering about problem of stopping logging before turning the device off. I read other review (I can't find the link, now), where reviewer couldn't download any data from M-241 (file(s) were 0 bytes long). He suspected that it was due to battery died while logging.

That seems to be consistent with manual, at least. I hope that future firmware upgrade will fix that issue, as I am going to give it a try, anyway.

Michal

[Stephen Hui]

Hmm curious, I wonder how accurate of a GPS receiver it is compared to say a Sirf III or other MTK based receivers. I am thinking this is a good car bluetooth GPS for my PDA but I'm not sure if it's a good replacement for my Holux GPS-Slim 236. The fact that it only works upright is a bit of a challenge too since that means I'll need a window mount for the GPS. I don't need it so much as a logger but I find the little display great for say a cycling odometer. :)

[Franco M. Lazzuri]

Please, anyone got it working with a NOKIA Phone (mine is Symbian/Nokia E90)? Please, I bought to use with google maps thru blutooth, but after a success pairing, it don't work receiving data. HELP, please.

[Matthias]

Hello, i also have a M241 device and had the following problems:

- When you download the logfiles to your computer, you can see (as mentioned above) two files. A google earth .klm-file and a .trl-file. If you got some waypoints in the long./lat.-menue you have aditional two files called Holux_M-241_Waypoints.kml and Holux_M-241_Waypoints.trl if your device's name is set to "Holux". If you download another log, be aware of the software overwriting the old waypoint-files.

- With the Holux Logger Utility software you can convert the .trl-file in other formats. e.g. NMEA but you only get the GPRMC-tags without altitude information!!!

"$GPRMC,115518,A,5033.8xxxxx,N,829.9xxxxx,E,0,0,130308,,*14"

You can also choose TEXT format which gives you information about the altitude (in Meter)

"8.30xxxxx,50.52xxxxx,205.02,Thu Mar 13 13:09:08 2008"

At least the GPX format (xml) (without altitude) :-(

"... gpx version="1.0" ... trkpt lat="50.5xxxxx" lon="8.4xxxxx" ... time ... 2008-03-13T11:51:54Z ... /time ... name ...![CDATA[Point 0]] .../name ... /trkpt"

- Another thing - the device does't function in the southern hemisphere (http://www.plumbargains.com/wordpress/index.php/2008/03/13/holux-m241-gps-data-logger-receiver/)

greets from germany
Matthias

[Tom]

Hello,
I had no success transfering the data from the M241 to the PC.

Firmware V1.6 (with german language)

No success via Bluetooth:
OS: Windows 2000SP4 and XP SP2

via USB ok only on XP, not via bluetooth

Can anybody help me?
tom

[xtemujin]

I'm also not able to use the Holux M-241 with my Nokia E61i.

The E61i is able to BT pair with the M-241 but does not work with the Nokia navigator where it'll show the satellite status.

I've taken some photos of the Holux M-241.

http://www.flickr.com/photos/xtemujin/sets/72157601590395648/

[Matthias]

Hello folks,

here you will find a software package that contains a new USB driver, the new HOLUXLoggerUtility and firmware 1.11 in english. Hope that will fix the problems on the southern hemisphere.

ftp://ftp.holux.com.tw/products/products/M241

The output format .gpx now has altitude information.
The NMEA txt-file not :-(

Is there anybody who can test, if the device now works correct on the southern hemisphere?

@tom
Hast Du wirklich die Firmware 1.6 auf deutsch? Kannst Du mal probieren, ob man mit dem neuen HOLUXLoggerUtility die Firmware sichern kann? Wenn ja, würde ich mich über eine Kopie freuen :-)

Matthias

[xtemujin]

I've tested a few GPS programme with my E61i and the Holux M-241.

No go with Nokia navigator, SmartcomGPS, MGmaps and Agis AsiaMaps.

It does work with Trek Buddy and Nav4all.

HTH.

[David Clapp]

Firmware 1.11 includes an "autolog" setting to eli,inate the extra, manual step to start logging.

It also includes 1 Hz time logging.

[Herbert]

I´ve just bought one M241, but it didn´t work with batteries... I bought new alkaline batteries, but nothing happened, only works with the car adapter or connected to PC... does anyone knows what could it be?

[xtemujin]

I'm finally able to use the Holux M-241 with my Nokia E61i.

I need to delete all my previously paired GPS in the BT Paired Devices.

The Holux M241 now works with all the GPS software on my E61i.

I'm now using AFtrack to check the satellite status instead of using the Nokia Navigator.

http://www.afischer-online.de/sos/AFTrack/

HTH.

[Manvendra]

I applied the firmware 1.1. I am not sure what happened but after the upgrade, my bluetooth address has become 00:00:00:00:00:00. But the GPS receiver is working and I can use it using the usb cable. But i am not able to connect to the device using bluetooth. Any idea on how to set the bluetooth address on the device.

[Zulu]

The logging feature works fine here in Australia, so it looks like the "southern hemisphere" bug is fixed in fw 1.11.

[countjocular]

Just tried using the latest BT747/iBlue747 pc software to access the Holux M-241
http://www.transystem.com.tw/p-gps-iblue747.htm
Not checked it out fully yet but seems that I can modify the Holux settings from the pc, and a nice surprise is the M-241 LCD screen setting options have changed to include an autolog and backlight option. Powered up the M-241 on its own and the position logging started automatically upon getting a fix, and the backlight stayed on for 60 secs as I wanted also.
Cheers,
Countjocular

[Vitor_BR]

some considerations:
1- I upgraded to 1.1 firmware and i'm using it in southern hemisphere normally
2- The firmware upgrade sw tells you if the upgrade procedure is unsuccessf8l, you may lose your BT address. to fix you must upgrade again using the SAME COMPUTER you upgraded it the first time (since it saved your address there, i think)
3- i also confirm the new autostart mode works well