This is a MIDI wind controller. It includes a pressure sensor whose output is translated into MIDI NoteON wtih Note Velocity data. Four computer keyboard style pushbuttons set the Key Value based on brass fingerings. Three more pushbuttons set the octave, and one last pushbutton enters the value of the other 7 buttons as a MIDI Program Change. The back of the horn provides MIDI Controllers operated by the two thumbs. There are four pushon/pushoff buttons and two joysticks.
The Horn is connected by cord to a single board microcomputer. The micro is programmed in Forth language.
A PDF file describes the circuitry and programming of the horn along with a discussion about the advantages of Alternative Controller Devices over their acoustic counterparts.