Yellowed vintage CASIO calculator restoration. Retrobright Magic

Casio FN-20 VFD Calculator.1985 Prooducted.
Not working in bad shape.
Fully disassembly and restore.
00:00 - 03:59 Disassemble
03:59 - 04:35 Clean
04:35 - 05:23 Retrobright day1
05:23 - 06:00 Retrobright day2
06:00 - 09:11 Fix & Assemble
09:11 - 10:52 Demo

After long time exposure of sunlight.
Calculator's upper panel brittled and cracked.
So keys stuck by pieces panel and fall apart when disassemble.

Board self is OK.Little wipe and clean is perfect.
But button conductive layer is always active and don't recover due to
key is pushed for a long time(Stack something on keys maybe).
Bent the layer back made things live again.

Retrobright process use 12% hydrogen peroxide solution .soak for 2-3 days to fully turn it white.
The keys also yellowed so I tried to retrobright it too.But half day of process just made color faded uneven.Learned it ;D

Video shot by a old DSLR.Sorry about the focus issue.
Hope you enjoy it.

Видео Yellowed vintage CASIO calculator restoration. Retrobright Magic канала AccorK EL