This is the QSL I am currently using. The shot was taken during a skydive over Strasbourg/France (Photo by Hans Knauss). It doesn´t seem to be possible to get permission for /AeroPortable operation (it was never done to my knowledge) - maybe one day !? For this jump, the battery box of the Standard C-500 was empty, and it would have been hard to turn up the volume enough to get louder than the wind noise at 200 km/h...