I'm not sure I understand this. Are the GSM prototypes with which you are familiar, FINISHED prototypes, i.e. same size, circuits, etc, as the final product? If so, I'd understand the difficulty, but that is a form of prototyping that I'm only familiar with through the efforts of non-technical people to get involved in the hi-tech field. I guess it gets done that way a lot, and this is likely the source of the devices we swear at. Usually, the prototypes I've developed, are what we refer to as level-1 prototypes. They demonstrate the basic concept as being workable. At level-2. you bring in accountants and marketing people to work with the engineers to see if the device can be produced in a cost-effevtive manner, wherein the beanheads determine that they'll actually be able to make a profit promising designs die here because the engineer won't let the beancounter substitute that switch that will break at the device's half-life, or because the engineer won't let the marketing guy make the device purple and yellow. Good for the bloody engineer, too... -dq