Security for Mafiosos and Freedom Fighters

Peter Fairbrother zenadsl6186 at
Thu Jul 17 04:12:12 PDT 2003

Bill Frantz wrote:

> Ever since I heard that manufacturers were cleaning assembled boards with
> soap and water I have wondered just how much you need to protect electronic
> circuits from water.  You obviously don't want to allow them to stay damp
> so they corrode, but immersion for a time (up to weeks) followed by a fresh
> water rinse and drying might not be so bad.  Do any hardware experts have
> an opinion?

A long time ago I used to teach an "intro to computing" class. many students
were older people who were afraid to physically touch a keyboard - partly
just because it was unfamiliar, because it meant they were actually, now,
starting on the road to learning, because they feared to "break something",
or because they thought they might get a shock (I kid you not). I digress.

One way of making them feel more comfortable was to "accidently" spill a
drink on a keyboard, than immerse it in a sink, rinse, and hang out to dry.
Sometimes I used a hairdrier to reuse the keyboard during the lesson, but
mostly I just left it overnight to dry. That gave some at least of them some
confidence that it was ok to touch the keyboard.

I've also washed an iMac (which had fallen in the sea) by immersion in tap
water and careful drying, the CD needed more care (drying with IPA), I took
out the hard drive first and was careful with that, also cleaned all
connectors with solvent cleaner, but it worked ok afterwards.

BTW, do NOT do this with crappy Apple keyboards! They are membrane-based and
will be destroyed. They are also hard to open for repair, and when I asked
an Apple chap about them he said "You should never drink near a keyboard".
What crap!

I give no guarantee that it won't destroy your keyboard, but it won't hurt
most keyboards.

Peter Fairbrother

BTW, m-o-o-t uses a randomised virtual keyboard with TEMPEST (both EM and
optical) resistant fonts. It's okay for inputting keys, but it's a hassle
for inputting text.

Which means that your keys might be safe from keyloggers (both hardware and
software), but your plaintext isn't. Sigh. I'm trying to improve it by
putting the "senhorita" letters in one block and the rest elsewhere (not for
key input obviously), and you do learn where the keys are after a while, but
it's still a hassle.

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