BT747 is Software for GPS Data Logger Devices

  • Download recorded GPS Tracks
  • Workaround for GPS Week Number Rollover Bug
  • Compatible with most GPS Data Loggers or Tracking Devices using the MTK chipset.
  • Convert GPS position data in many formats (HTML (Google Maps API), GPX, KML, KMZ, ...)
  • Geotag JPG pictures and position any other filetype on the map (voice, documents, ...)
  • Handheld Devices (Palm, WinCE, Mobile Phones supporting Java (J2ME)) support
  • Desktops (Windows, MacOSX, Linux flavors) support
  • Configure MTK Chipset Based Devices and GPS Loggers
  • Real Time Tracking as explained  in GPS Tracking
  • AGPS(EPO) data upload to MTK II Chipset Based Devices and GPS Loggers (2.X version).
  • Bluetooth support (within some limitations)
  • Upload to OpenStreetMap directly for fast access to your tracks while mapping

Install BT747 GPS Data Logger Software or get a zip file (including source code). 


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GPS Week Number Rollover Bug - Workaround for GLOG 760 (and others)

The Transystem GLOG 760 Logger is affected by the GPS Week Rollover Bug for recordings in memory.  The values read in real time from the virtual serial port over USB are correct.

As a result BT747 was reporting no recordings in the log file as the reported date was in 1999 for recent recordings.

This was changed in BT747 V2.2.1 .  This version accepts dates starting from 1980 and - more importantly - it adds 1024 weeks to any date before 1/1/2009.


mdeweerd's picture

New AGPS URL

Sun, 08/05/2018 - 03:26 — mdeweerd

A new version of BT747 was released integrating a new AGPS download location.

The application has also been signed with a new signature, https://soft.bt747.org has been updated with these signatures and the jnlp files have been updated to use https.


mdeweerd's picture

BT747 - New code signatures

Sat, 02/13/2016 - 15:41 — mdeweerd

The code signing key used for BT747 had to be upgraded to SHA-256.

Unfortunately that also revoked the old key and apparently the timestamping was not properly done with the previous signatures.  So the java laucher complains that the certificate is revoked.

All files have been resigned and republished.

You may need to launch:

javaws -viewer

[on windows : "Windows Key + R" to access the execute popup where you can enter this].


Physikator's picture

Wanted: small tracker with display and large memory

Sat, 03/09/2013 - 21:40 — Physikator

I currently use a Holux M241, and the features I like most are

  • AA battery: you can get them anywhere on this world
  • Display showing coordinates or velocity or distance
  • Good cooperation with BT747

However, the memory for 131000 track points (less with newer firmware) is a bit tiny for any holiday of more than a week.

I found the "Locosys GPS Walker" with about 2 GBytes of Memory (and a built-in mp3-player, who needs that?), but that thing has some disadvantages:


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