[OSM-talk] NaviGPS Units for the Foundation

Joerg Ostertag (OSM Munich/Germany) openstreetmap at ostertag.name
Mon Sep 4 18:30:21 BST 2006

On Monday 04 September 2006 18:43, Etienne wrote:
> On 9/4/06, Mikel Maron <mikel_maron at yahoo.com> wrote:
> > I've just ordered 5 (everything they had in stock) from storage depot,
> > which took 10% off up front and free shipping, as a donation to
> > OpenStreetMap.
> > If they get more in between now and Thursday, I'll order more. This
> > Saturday will be the first outing for these OpenStreetMap Foundation GPS
> > units.
> >
> > Total is 290. I'm fine covering this myself .. but really do welcome
> > anyone throwing some cash my way to spread out the expense.
> Mikel
> Well done!

Yes Indeed; Great!

> Some tips for getting the most out of them on the day (given that you
> probably won't have much time to play with them beforehand):
> - Set the track logs to record at 1 second intervals.  

Setting the recording to 1 Dataset every second gave the best results here 

> This will give 2 hours recording using the built in memory.  Ask people to
> return to base every two hours.

Well since I bought 5 NaviGPS for the German Users, I do have some feedback 
from the people using them here.
I personally think you should definitely use them with SD-Cards.
But I also know that you sometimes have problems with them, using larger 
SD-Cards. So you should stick to SD-Cards with max. 1GB. The Problem is 
larger/cheaper SD-Cards tend to only work with 3.3V and the NaviGPS only 
provides 2.8V to the SD-Card Slot.
The Benefits of using SD-Cards are:
 - You can log a complete NMEA set:
    - including PDOP,ALT, num satelites, ...
    - it's about 250MB for 2 Week of daily track collecting
 - You don't need any Special Windows Application to read from the SD-Card
   Every PC with an SD-Card Adapter (reading VFAT) works
 - Your Track collectors don't have to come back every hour
 - you can use osmfilter to directly read these Files and convert them

I personally found that using SD-Cards with maximum 1GB worked best. I never 
got a larger Card to work properly for a longer period.

> - If you have any old SD or MMC cards then stick them in (and switch on
> logging).  Even a small 64Mb card will increase recording time
> dramatically. 

Even a 16MB Card should last a complete Day in full resolution ;-)

> - Enable SBAS.  You also need to make sure that the unit is 
> set to Normal power mode.  In low power mode the SBAS is disabled
> automatically. 

Aaah that's the difference in Low Power Mode ;-)

> - If they are fully charged they should last the whole day 
> without any difficulty.

And one more thing:
After switching them on always check the following:
 They must say:
    "NEW FILE"
After a short time they must Beep  (If Alarm-Buzzer is set on) to tell you 
that you have reception and a LOCK. This is important, because sometimes (one 
out of 10) they don't get a lock an never start logging. If this happens you 
can simply switch them off and on and try again. Most of the time this helps. 
Looking at the Filesize on the SD Card doesn't help to recognize this, since 
the NaviGPS always logs NMEA Sentences; but they only show 000,000 as 
position so it will be useless. 
I think looking at the speed displayed on the Track Page might help to see if 
you got a lock, but I'm not sure if this always tells that they are logging 

If you want the people take the NaviGPS with them on a bike or while walking 
try to get some small arm-pockets to put them into. I'm thinking of those 
small MP3-player pockets. The Bike-/Arm-mounts where not delivered with the 
ones I got from Storage Depot.

Have Fun and good tracking with the NaviGPS.



PS.: If you have any questions about the NaviGPS which you think I could 
answer easier by Phone feel free to send me a personal e-mail and I can send 
you my telephone number too.

More information about the talk mailing list