Comments on: Evaluating the Holux M-241 data logger

By: Hotkamp

Hotkamp — Sat, 26 Dec 2009 15:58:12 +0000

in the meantime, Holux m-241 firmware 1.13 is published as well, which allows you to disable bluetooth, hopefully increasing the battery lifetime.

By: sdchew

sdchew — Mon, 10 Aug 2009 10:06:24 +0000

Actually, the M-241c is just the M-241 without bluetooth.

By: decebal

decebal — Wed, 29 Jul 2009 14:52:16 +0000

@Bruce thank you for idea to contact directly Holux

Actually there is a link to download the latest firmware, v 1.12, http://www.holux.com/JCore/en/products/products_download.jsp?pno=341

M-241 Firmware V1.12 update package (New) 2008-10-27 .rar

By: Bruce

Bruce — Wed, 29 Jul 2009 13:29:20 +0000

@dec you can contact Holux support here for a definitive answer. The latest firmware mentioned on the Holux website is 1.11; I see no download link for 1.12. Also looks like there's a new product, the M-241c—which probably means they'll loose interest in fixing any issues with the M-241!

By: decebal

decebal — Wed, 29 Jul 2009 11:58:41 +0000

Hi,

I recently bought Holux M-241. Despite its firmware is up to date (v 1.12) and found out from some reviews that in the latest firmware, such as v 1.11, that issue about corrupting log files if it's not closed before running out of battery, log files are still corrupted. I did it on purpose: after I noticed that battery runs out of energy by seeing its indicator, I didn't close the GPS to see what will happen. After the battery was dead, I did replace it with a new one, but unfortunately I noticed that I have some more memory, like I didn't use it before. Also, the mem. counter was not working anymore. The only fix I could apply (I had no computer by that time) was to ERASE all data from its memory by using its own user interface.

Well, could somebody tell me whether this issue was really fixed in the latest firmwares? .. or I was wrongly informed about this fix?

I have this nightmare: going to a long trip, logging each and every day and - by the end of the trip - forgot to check device/replace the battery .. all data is gone and replaced by a huge frustration :(

Many thanks,
dec

By: Patrick

Patrick — Wed, 17 Jun 2009 01:53:23 +0000

NiCad/NiMH batteries are a bad idea in a device such as this. They output 1.2v nominal versus the 1.5 volts a fresh alkaline cell can provide. A device like this most likely uses a boost circuit to raise the voltage to 3.3 (or perhaps even 5v) internally. Systems such as this fare extremely poorly when driven with 1.2 volts, regardless of the amp/hour capacity of the cells.

Despite it seeming to be counter-intuitive, you would likely get 2-3x the life out of plain old alkaline cells. The disposable high-cap lithium (1.5v) cells might work well here.

By: benjamin

benjamin — Tue, 06 Jan 2009 23:36:06 +0000

I bought the M241 some months ago for geotagging of a hike and it lasted between 7 and 10 hours with Sanyo Eneloops which I'd recommend to anybody because of the low self discharge. They're like a general recommendation in most photo forums here in Germany, I'd totally agree.

I used it with the software supplied connecting it via USB to my PC and was quite satisfied with the results. I used geosetter (http://www.geosetter.de/en/) to tag the photos - it didn't work with the kmls but the converted gpx files did the job.

Concerning the accurancy loss with low batteries: afaik the GPS-Antenna receives analog signals needing to be amplified before converting them for digital use. Lower voltage might affect the on-die-amp resulting in poor performance.

Anyway: I'd recommend the Holux after my experiences with it. Though it's not weathersealed it resisted light rain, cold and rough treatment. The accurancy was satisfactory for me and the built-in display is a gift when you want to know how much you've hiked. The ability to use AAs is very nice, too.

By: Andy

Andy — Tue, 04 Nov 2008 08:56:41 +0000

gpsbabel now supports the M-241. The command line makes it really simple (and fast!) to read data off and output it in KML or GPX. On the mac:

gpsbabel -t -r -w -i m241 -f /dev/tty.HOLUX_M-241-SPPSlave-1 -o kml -F `date +'%F-%H:%M'`.kml

(replace kml with gpx to get gpx)

By: Bruce

Bruce — Sat, 01 Nov 2008 20:01:38 +0000

@Wilber: Yes, the M-241 can record a track log and function as a GPS receiver simultaneously.

By: Wilbur Harvey

Wilbur Harvey — Sat, 01 Nov 2008 19:31:48 +0000

Can this unit log and nav at the same time, that is, can I record a log on the unit while at the same time view the navigation on my laptop over bluetooth?