I recently had the opportunity to test-drive the AMOD AGL3080 GPS Logger. For the past three weeks I've given the AGL3080 a run for it's money: I've tagged a few hundred photos, mapped a few hikes and plotted my commute.

And... I'm impressed!
My DG-100 has a serious contender for pocket-space in my future photowalks.
Here's why:

History

AGL3080 Front. 3 status LEDs: memory full, satellite lock, low battery.

AMOD has recently relaunched the AGL3080. Their first-gen release was sadly flawed and suffered from susceptibility to RF interference, making the GPS module inaccurate. AMOD seems to be pretty actively chasing down owners of their first-gen device and offering upgrades, so if you own an old AGL3080, you should get in touch with them! The new version works flawlessly.

Drivers & Formats

The AGL3080 is a driverless GPS logger, which means it mounts as a USB external drive. If you read my blog post about the DG-100, you know that driver issues with many GPS devices can be a #*$@!'ing nightmare, especially if you're on a Mac!

The AGL3080 saves each GPS track in NMEA format (although oddly enough, it gives each file a .log extension, so make sure GPSbabel doesn't get confused)

You can convert your log files into GPX format to use with GPS Photo Linker or HoudahGeo, or convert it to KML for viewing in Google Earth.

The device uses the SiRF III chipset, which, is the only chip I trust for good reliability & accuracy- especially in urban environments. (Recently, I've heard good things about the Nemerix chipset used in devices like the iBlue, but it still doesn't have the sensitivity of the SiRFstar III chipset, so no cookie for you.)

The SiRF III chip puts the AGL3080 as a front-runner among the small handful of GPS loggers worth considering.

Form & Function

AGL3080 Back. 3 AAA batteries for 15 hours of continuous use. No USB-charging, though.

The AGL3080 takes 3 AAA batteries for about 15 hours of use. It's very well built and it fits perfectly in my hand or in my pocket, however it's not as flat as the DG-100, so it doesn't stay put on the car dash quite as nicely. The battery-compartment door (frequently the first part to break on many of my devices) is rugged and easy to open. It has a built-in carabiener hoop, à la Sony GPS-CS1. Similar to the Sony, the provided carabiener and strap are junk, replace ASAP.

As I find myself slowly adapting to life in Japan, the carabiener hoop is begging me for a cute dangling cell-phone toy. Update on that to follow.

The device logs position, altitude, heading, speed, acquired satellites, hdop & vdop every 1 second and saves it to its 128mb of internal memory. It creates a new log file every time the power is cycled, so it's fairly easy to identify tracks if you're looking for a particular day's data.

Sample GPX output. The AGL3080 logs: lat, lon, elevation, heading, speed, satellites, hdop & vdop @ 1Hz. Impressive. Textmate screenshot using skitch.

Richard Akerman has identified an interesting quirk where the log files are missing the standard filesystem created/modified datestamps, though it doesn't seem to affect the data.

While 1Hz logging may be a tad on the excessive side, it certainly provides excellent resolution (although I would recommend using a quick GPSBabel filter to strip out excess track points within 5m. You can chop your GPX file size by about 70% with no reduction to your data.)

The AGL3080 won't recharge your batteries over USB like many other devices (somewhat dissapointing!) so go buy a good wall-mount battery charger. Your rechargeables will charge faster and stay healthy for longer anyway.

Bottom line

AGL3080 & DG-100. No surprise here; Both devices use the SiRF III Chipset for near identical results. Shown: Route 38 - Takikawa (滝川) to Ashibetsu (芦別), Hokkaido, Japan on Google Earth

Okay- here's the verdict. The AGL3080 beats the DG-100, hands-down, for one reason and one reason only. Data.

We geocoders are interested in collecting quality GPS data to tag our photos, videos, blog posts, etc. The DG-100 logs only a small subset of available GPS data (position, altitude and speed), while the AGL3080 logs position, altitude, speed, heading, acquired satellites, hdop and vdop (Dilution of precision... look it up.) USB-charging and logging frequency control are one way to evaluate a device, but if it doesn't log every single piece of available GPS information, why bother carrying it around with you?

Oh- and the fact that the AGL3080 will work on my Mac without spending a few dozen hours hacking around with a C script is pretty cool too. =)

You can get your hands on a AMOD AGL3080 through semsons, amazon.com or you can contact AMOD directly.

Review & Photography © Kevin Jaako, 2008. All rights reserved.