[CCTALK] RE: scanners & circuit boards..

From: Douglas H. Quebbeman <dougq_at_iglou.com>
Date: Thu May 16 22:16:38 2002

> > EPROMs don't have UV-opaque glass windows, they have
> > UV-transparent quartz windows. So they can be erased,
> > but not by casual exposure.
>
> Yes, but every flatbed scanner I've ever seen has a flat
> piece of glass on top (which is optically between the lamp
> and the object-being-scanned). I can't believe they used
> any special glass that was even moderately transparent to
> UV -- it would be expensive and pointless.

But regardless, scanning would be causal exposure, and such
exposure (even if that glass were UV transparent) would be
unlikely to be able to hurt the EPROM.

But the only boards with EPROMs I've ever seen that *didn't*
have labels covering the windows were ones I did myself or
ones where the label glue had dried up and the label fell
off.

FWIW, I usually use silver write-protect tabs or the black
vinyl ones for this purpose; I'd only use white paper on
stuff that shipped so I could write a version number on them.
Dunno if the tabs are available anymore, but I think I still
have a supply...

-dq
Received on Thu May 16 2002 - 22:16:38 BST