Datalogger Royaltek RGM-3800
The Royaltek RGM-3800 is an inexpensive GPS receiver with a USB port capable of functioning as either a stand-alone GPS track logger or attached to a computer. It comes supplied with the following:
- a small instruction manual in English, French, German, Italian and Spanish,
- an 8 cm CD with software and drivers for Windows
- USB cable for communication with a PC (USB to Mini-USB)
- a manual in PDF format
- clip and short lanyard
Startup
The unit requires 2 AAA batteries to operate, which can be 1.2V NiMH rechargeable cells. When switched on the logger immediately proceeds to acquire a GPS fix which takes about 40 seconds from a cold start. During this process the LED on the top blinks green. Once GPS position is acquired the unit begins logging position, time and certain other data to built-in non-volatile memory and the green light stops blinking and glows continuously. It's best to stay still as long as the device finishes first acquisition phase if not that will be extended and the first GPS points can then be dispersed over several kilometers (observation practice when used by car). The power button can be pressed again to stop the GPS logging, and then again once more to start a new track. The interval between each GPS position logged is set by a factory setting of 15 seconds, but can be changed to other values.
Configuration
The unit offers the following settings:
- Logging interval from every 1 second to every 60 seconds
- Recording modes:
- 0 lat, long, time (12 Bytes)
- 1 lat, long, time, alt (16 Bytes)
- 2 lat, long, time, alt, vel (20 Bytes)
- 3 lat, long, time, alt, vel, dist (24 Bytes)
- 4 lat, long, time, alt, vel, dist, status (60 Bytes) (latitude and longitude, UT timestamp, altitude, speed, distance, reception quality / satellites)
- Behavior when the memory is full: stop recording or discard oldest points to make way for new records.
Maximum duration of recording
| Mode | Bytes | Samples | Logging interval | ||||
|---|---|---|---|---|---|---|---|
| 1s | 3s | 5s | 10s | 30s | |||
| 0 | 12 | 699008 | 8 days 2 hrs | 24 days 6 hrs | 40 days 10 hrs | 80 days 21 hrs | 242 days 17 hrs |
| 1 | 16 | 524288 | 6 days 1 hrs | 18 days 4 hrs | 30 days 8 hrs | 60 days 16 hrs | 182 days 1 hrs |
| 2 | 20 | 419328 | 4 days 20 hrs | 14 days 13 hrs | 24 days 6 hrs | 48 days 12 hrs | 145 days 14 hrs |
| 3 | 24 | 349440 | 4 days 1 hrs | 12 days 3 hrs | 20 days 5 hrs | 40 days 10 hrs | 121 days 8 hrs |
| 4 | 60 | 139776 | 1 days 14 hrs | 4 days 20 hrs | 8 days 2 hrs | 16 days 4 hrs | 48 days 12 hrs |
Software
The included software is for Windows but operation under Linux and MacOS X is possible too.
Windows
The manufacturer "Royaltek" provides software for Windows only on the supplied CD (and by download from their website).
- all the functions of the recorder's supported (including modifying the logging parameters)
- Cons: The software display window is too small and it is not possible to change it. However the small size of the window makes it fully visible on even the lowest resolution laptops :-)
Linux
The recorded logs can be retrieved using the rgm3800.py Python script.