Walkie One Concept 1.2 R7 microphone fit reference

Manufacturer source: https://github.com/adafruit/Adafruit-I2S-Microphone-Breakout-PCB
Retrieved 4 September 2026. The original Adafruit Eagle board, README and license are included here without modification. Design credit: Limor Fried/Ladyada for Adafruit Industries. See license.txt for Creative Commons Attribution-ShareAlike terms.

R7's derived microphone fit reference adds the acoustic PCB bore omitted from the supplied component proxy, corrects the MEMS package orientation to the manufacturer's footprint, and removes the proxy's decorative rear port bump. These corrections and the placed rigid transform are implemented in code/mic_reference.py. The manufacturer's license and attribution accompany this derived fit reference; they are not a license statement for unrelated case geometry or user artwork.

Eagle board outline center: (9.271,6.350) mm. IC1 at (9.271,7.112), rotation MR180. Package acoustic pad3 local (0,-0.71), drill1.025 mm. Thus bore center relative to board outline center is (0,1.472) mm.

Place the corrected reference by rotating 180 degrees about Z and translating to (0,-21.528,7.95) mm. Acoustic bore is then centered at world (0,-23). The bare PCB face points toward the front. The extra REF_microphone_PCB_ACOUSTIC_CHECK.step is a diagnostic PCB-only model for verifying the open path, not a manufacturing part or an extra purchased component.

The complete original user-supplied microphone STL is preserved in source_inputs. PCB thickness, passive envelopes and wire terminations require confirmation against real purchased hardware. No pin header or soldered harness is modeled.
