BT747: Read and set GPS Logger

Use the free BT747 software to read out and configure the GPS logger. And this on both Windows and Mac computers.

In my previous GPS logger practice tests is always noticed one thing: Often there are problems with the included software. In this article I would like to introduce a reliable alternative program.

For most Geotagger who use the GPS chipset from MTK, the open-source software BT747 can be used. Written is the tool in Java and thus platform independent.

Features of the BT747 control program

The tool for GPS devices can essentially do two things, reading the memory and settings on the logger.

In addition, converting tracks to other data formats, updating GPS assist data (A-GPS) and geotagging data.

Prerequisite is a MTK chipset in Geologger. More specifically, it knows the detailed list of compatible loggers . Even I have successfully used BT747 with the GPS loggers i-Blue 747A + and Holux M-241 .

Installation of BT747

BT747 installation

BT747 installation

BT747 is available for free download . In addition to a desktop variants, BT747 is also available for mobile devices. Among other things, for (the old) Windows Mobile and J2ME phones.

The easiest way to install is with Windows. Just download and run the desktop version for easy installation. That’s it.

On the Mac, it gets a little bit more complicated because the installer lacks rights to create a directory. The mean thing is that no error message comes. Before the installation is started so first start the terminal and enter the following two commands one after the other. The administrator password is required.

sudo mkdir / var / lock sudo chmod 777 / var / lock

The first command creates the folder, the second makes it readable and writable. Then load and start the installer as with Windows.

Connect logger

If the logger is to be connected via Bluetooth, the Blutooth connection must first be established in the operating system. Then look for the used COM port. For Windows, this is done via ” Control Panel – Change Bluetooth Settings – COM Ports “. For Mac simply select “Bluetooth (Mac)” in the Connect dialog.

For a USB connection, the drivers must first be installed.

The ” Connect ” button at the bottom connects the BT747 to the GPS-Logger.

Download the GPS tracks

On the “Log Actions” screen, information about the connected logger is displayed on the right. Interesting here is the current memory usage.

BT747 control program

BT747 control program

The download of tracks runs from top to bottom.

In the files box, the file paths for the raw data and the converted tracks are created first.

Continue to download the raw file with the “Download” button.

Finally, convert the track on the computer into the desired geodata format.

For example, to convert to GPX universal format just press the “GPX” button. Then you have the data in the most universal format such as geotagging with GeoSetter or Lightroom on the computer.

Delete old tracks

Delete GPS logger

Delete GPS logger

After the tracks are on the computer and checked if everything fits, the logger can be prepared for the next tour. To do this, switch to the tab “Device settings” and release the memory from the logger with “Delete only”.

Configure GPS Logger

For device settings, two digits are particularly important.

BT747 control program device settings

One is the ” Position” area on the left.
Here you can set which data will be saved. Most important effect: Number of records to be saved. Very nice with the BT747 application is that immediately the estimated number of records is displayed. Longitude and latitude are mandatory here. Possibly. still activate altitude. Thus, the available data storage is optimally utilized for geotagging.

On the other hand ” Log of …” bottom right.
There, the log distance is adapted to personal needs. Fix should stay at 1 second (1000 ms). For geotagging, a time interval of 5 seconds has proven to be a good compromise between accuracy and memory requirements.

Update A-GPS

BT747 control program AGPS

BT747 control program AGPS

The AGPS Screen is very clear. Using AGPS data to save the logger, the file is first downloaded from the Internet and then transferred to the logger. The data is then valid for one week.

With current AGPS data, the time until the GPS fix is ​​significantly reduced.


Big advantages are the platform independence and the huge range of functions. Beginners may find it difficult to do so with the full and un-intuitive interface. Due to the many professional setting options, there is also the risk of making unfavorable settings on the logger. Under Windows, BT747 is my favorite tool to read and set GPS-Logger.