Documentation for the 2006 Trans-Atlantic Balloon Flight

This page contains documentation for instrumentation and software to be used in a balloon flight from Sweden to Canada in summer 2006.

The telemetry document (1) describes the format of a telemetry frame and how to recover accurate timing information.

The interface board is unique to this experiment. The schematic (2) shows the interface to the Dartmouth photometer, the telemetry system, the power systems, and the Santa Cruz magnetometer. A complete layout of the board is included in case connectors need to be re-wired (3 and 4). As delivered, the interface board is configured to be run with regulated 5V supplies. A DPU board and pulse height analyzer board comprise the remainder of the electronics in the electronics box (5).

The ground station is simply a PC running a LabWindows program. The LabWindows source and uir code are included (6), as well as a Windows distribution kit (7). For convenience, unzip and install the gse software in a directory on the desktop rather than the default location. Then set up a DOS window that opens in that directory and place playback files there too. For playback, the data file should consist of complete telemetry frames. NSBF-formatted data should be pre-processed by XORing data with 0x5555, and removing NSBF-supplied data headers. A data file acquired during testing at UW is supplied for testing the software installation (8). To play back a data file through the software, type the command swgse filename in the DOS window. In this mode, the software plays back at roughly 4 times faster than real time. To monitor data coming in through a COM port on the PC, type swgse. When monitoring the COM port, the software will archive incoming data frames in a file named swgse.dat. This file will be over-written each time the software is run, so the file should be immediately re-named if it is to be kept.

The DPU softare is also included for reference (9). This software runs on an ADSP-2101 digital signal processor, and is written in the assembly language of that device.


  1. Telemetry documentation (32KB pdf)
  2. Interface board schematic (380K pdf)
  3. Interface board bottom layer (161K pdf)
  4. Interface board top layer (158K pdf)
  5. Electronics box footprint (13K pdf)
  6. gse source files (10K zipfile)
  7. zipped distribution kit (5.6M zipfile; WIN98 or later)
  8. data file (290K raw tm file)
  9. DPU source code (34K text file)