Hi everyone!
I wanted to share one of my recent bench projects: saving a rare 1993 Casio AW-330-AT (Module 734) altimeter watch that I bought at an online auction for ~$11.
It arrived in pretty rough shape—completely dead, filled with leaked battery acid residue, a ruined LCD, a stuck analog gear train, and no strap.
Restoration & Repair Highlights:
- Chemical Cleanup & Circuit Revival: Neutralized heavy battery acid corrosion using IPA, then re-aligned the internal ground springs to restore continuity and get the AC reset firing again.
- Un-sticking the Analog Movement: Carefully worked the 30-year-old mechanical gear train back and forth to clear mechanical resistance.
- NOS Display Swap: Located a New Old Stock (NOS) gold-tinted LCD screen from a seller in Spain to replace the damaged original display.
- Custom Screen Protector Hack: I traced the irregular glass contour using Tesa tape, digitized the vector pattern, and custom-cut a hydrogel screen protector.
- NOS Strap: Sourced an original Casio "Altitude" mountain-motif strap on eBay.
The Ultimate Validation:
To test the barometric sensor calibration, I took the watch on a hiking trip up to ~3,000 meters in the Austrian Alps. The altimeter tracked elevation flawlessly throughout the climb, staying within ~5 meters of official topographic map benchmarks!
It went from a discarded piece of 90s electronic junk back to a reliable mountain tool.
UPDATE: This project was actually just featured on Hackaday!
Full step-by-step restoration write-up with high-res macro photos:
https://bench-journal.vercel.app/casio-aw-330-at
Edit: removed the misleading sentence about the screen protector.