||Figure 1. A working PS/2
prototype. It's much bigger and more awkward than a
production unit would be (but not as heavy as this picture seems to
suggest!). The 1-chip circuit board is inside the plastic pipe.
Production circuitry can be much smaller.
||Figure 2. Back view. From this
angle a manufactured unit would be nearly invisible.
||Figure 3. This is a key-side view of
the intact king pin-style prototype shown above. The keys are
bits of vinyl tubing glued crosswise on the roller arms of "basic
switches." The king pin nut is visible at the top as is the top
brace pad dangling from its hook. The bottom distal palm pad is
the cresent-shaped object at the bottom. The wooden piece
extending right at bottom is the proximal palm pad.
||Figure 4. A key-side view of naked key
decks prior to mounting the switches and circuit board. The
incomplete assembly is resting on the thumb brace (the folded piece of
blue mouse pad at bottom left). The top pad shown is smaller
than the one in the picture above. All three palm pads are
visible. The upper palm pad is another piece of mouse pad wired
to the deck spacers. The top pad is retained on the hook by a
twisted piece of small, solid wire.
Figure 5. A bottom view of the intact unit. This view really makes apparent the general lack of craftsmanship. Again the unit is resting on the thumb brace.
Figure 6. An unwired unit in hand. Keyswitches 0-5 are mounted but the pcb is missing. At this point I was unsure whether to mount the seventh switch, i.e. switch 6 (for the little finger), on its own deck or on the bottom of the ring finger's deck. I decided on the fourth deck thinking that otherwise switch 6 would be too vulnerable to damage. If I squint, this picture looks more like an actual production unit to me than do the pictures above.
||Figure 7. This is an example of my
previous generation of prototypes. I used this one for over a
year. The frame is folded from one piece of corregated
cardboard. The switches are on c-rings that slip around the
plastic pipe that holds the circuit board and are then glued in their
optimal positions. This one has an extra switch for the little
finger which is quite workable but unneeded. It's less
adjustable than the present generation but lighter.