First update — what we built this week

Welcome to the build log. This is where we'll post short updates from the workshop — what got built, what broke, what's queued for next week.

What we built

• Soldered the first audio path on a breadboard. Spotify plays through the I2S amp into a 1 W speaker.
• 3D-printed the first case shell in PETG. The screen window is the right size; the keypad cutouts are 0.4 mm too small. Reprint queued.
• Wrote the T9 driver for the matrix keyboard. Multi-tap works; predictive comes next.

What broke

• The first SIM7600 mini board wouldn't enumerate over USB. Swapped cable, swapped board, eventually swapped the host kernel — turned out to be a cdc-acm quirk on Pi OS Lite. Documented for the next twenty units.

Up next

• Pair Bluetooth headphones to the device. A2DP is built into the Pi Zero 2 W so it should be a userspace-only fix.
• Cut the second case shell with the keypad fix.

Thanks for reading. Replies welcome — hello@sparrowedition.com.