Voyager design history?

[naddy]

(10-19-2024 09:54 PM)naddy Wrote:  The hardware platform and function set of the 11C make such a perfect package that it seems obvious to me that this model was the primary design, and the other models were secondarily derived from it. The starting point appears to have been the goal to have all the functions of the 34C—minus the high-end SOLVE and ∫ features—but with enough keys for a more reasonable two shift levels rather than the 34C's three.

As I keep thinking about this, it strikes me that SOLVE and ∫ may actually have been part of the original design that became the 11C. Maybe marketing intervened and had those functions reserved for the future high-end model. Or maybe, more prosaically, they ran out of ROM space. (Is the 11C ROM full?) I imagine there was a short list of functions that had never made the cut because there was no key to spare, and Pyx/Cyx came out on top and replaced SOLVE and ∫.

This would go some way to explain a minor puzzle: the illogical placement of →R/→P on the 11C. You would expect them to be on the 1 key, next to the other conversions. Instead it looks as if they had been displaced when Pyx/Cyx were added and somebody made the decision to group those with the statistical functions. When the 15C freed up keyboard space by moving comparison ops behind the TEST prefix, →R/→P were moved to their logical—and quite possibly originally intended—position. There may have been knock-on effects on the 11C. I'm starting to picture an early 11C design that had SOLVE and ∫ where the 15C has MATRIX and RESULT.