DigiTwist is an experimental 2 axis satellite tracker, primarily for the HamTV transmitter on the ISS. 2 broadcast satellite dish positioners are connected together and are controlled by a dual Diseqc pcb.
It is experimental in the sense that the satellite positioners were never meant to be used in this way and may fail. Development is continuing, particularly as to the size of the dish that can be carried. It has not yet received the ISS, mainly due to lack of opportunity.
More construction details, for early adopters of the test version of the Diseqc control pcb, will appear here shortly.
A presentation was given at CAT17: https://www.youtube.com/watch?v=qC8CSi8kZTs