Front view
The case is actually black but appears a muckier shade of brown in these shots. Note the relocation of what was the centre select/set key to the top right corner for ease of operation with gloved hands!
Side view
Looking at the altimeter from the top, the serial port and power switch are both visible.
Rear view
Not the most exciting of shots, but the battery compartment does work and the hole for the piezo sounder is aligned! The side switch is also visible, currently used as an in-flight shortcut to disable the sounder.
Internals
A lot more interesting. This is with the rear cover removed and is the final prototype with the loud 74HC04 piezo drive and return to a 4MHz crystal / 1MHz resonator drive. The printed circuit board and schematics in the hardware section incorporate these modifications.
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