The Gilbert 21 Project
Personal Biological Recording Software
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In general, a data logger is an electronic instrument which records data over time. Here the term is used to describe an instrument which records location information over time - a GPS data logger. GPS stands for Global Positioning System and many biological recorders will be familiar with hand-held GPS units, such as the Garmin eTrex, which make the business of getting Ordnance Survey grid references for biological records much easier than reading them from maps. GPS data loggers - such as the one descibed below - are different from a conventional hand-held GPS like the Garmin eTrex in that there is no visual display. In the field you cannot use one to read off your current location (unless you link it to a device like a computer running suitable software) - instead location information is logged to a file stored on the device which you can use later.

The Visiontac VGPS-900 data logger (also marketed as the Columbus V-900) was the only GPS data logger with the ability to record voice that I could find on the market when I was searching in the spring of 2010. Indeed it was marketed as 'the worlds first GPS data logger with voice recording function.' The Gilbert 21 software is designed specifically to process the files produced by the this data logger and will not currently work with any other device, although it can be used without a data logger.

The best deal I could find when I bought my Visiontac VGPS-900 was with a Californian company called At that time the price was $90 (at the time of writing -  Feb 2011 - they are marketing it for $95).  Postage from USA was another $29 dollars. Incredibly, the device arrived with at my house in Lancashire two days after I ordered it via the internet (and a friend's experience matched my own). Because the device was imported, a bill for about £13 import duties arrived some weeks later. The device also comes without the required Micro SD card for which I paid about £10. But all in all - at something under £100 - I still a considered it to be good value.

If you are considering buying one of these devices, you should do a search on the internet for both the Visiontac and the Columbus devices (same device, different name) - you may find an even better deal now.

The Visiontac VGPS-900 comes with some software that enables you to make KML files that you can view in Google Earth - you see the track of where you've been and you click on the symbols that show where you made voice tags and play back whatever you said, but it is a long way from this to get to a biological record. That's where the Gilbert 21 software comes in.