Our work on the flight hardware made a great leap forward in the last weeks. So we are proud to be in time for designing and building the flight hardware for the ISU launch on the 13th of August.

new telemetry transmitter with printed board

After some weeks of very satisfying operation of the telemetry transmitter TTDO-1 we changed from the prototype board to the new printed circuit board. After reassembling all parts the transmitter is also working fine and we will go in production of the real flight hardware within the next weeks. Also a new GPS receiver was tested. This new GPS module GT-320FW has a special high-altitude firmware version loaded to support operation at altitudes in excess of 25 kilometres. The biggest advantage to the before used Garmin GPS 18 is the reduced weight of only 20 grams.

One of our biggest problems is to find calibrated pressure sensors for the pressure interval between 1mbar and 1100 mbar. There exist some sensors with the desired pressure interval but they are not really calibrated for very small pressure, only for standard pressure. New telemetry transmitter with printed board For calculating the real transfer function between pressure and output voltage, two different vacuum chambers were build, were we can measure exactly the coherence between pressure and output voltage in the requested interval.

Furthermore we are working on a calibration for the Geiger Mueller Counter. This will be done with a piece of sparse X-ray emitting stone. The Geiger-Mueller counter module was calibrated with a piece of Columbit. This is a poor gamma emitter with a radiation five times more than the background radiation in Vienna. We will compare the output of a well defined Geiger Mueller counter with that of our own counter.

One of the two vaccuum chambers

One of the two vaccuum chambers

The carbonfiber-styrodur structure of the first capsule is almost completed. The integration of the instrumentation modules has started. The shape of the first sherpa capsule is an ashlar with the dimensions of 22cm x 22cm x 11cm. The launch mass will be less than 1kg.