This can be dangerous, however - using a home made grounding strap.  A
properly built grounding wire/wrist or ankle strap has a resistor built
into the circuit.  One is not directly connected by the conductor to the
computer or case - whatever you connect the alligator clip to.  If too high
a current passes through the grounding strap resistor, it opens up thereby
breaking the connection (and protecting the wearer).  I don't recall the
resistance but from what I understand, the resistor acts like a fuse - a
"fuseable" resistor.  That is, it opens when current beyond a certain
amperage tries to pass through.

Personally, I take advantage of the ground provided by the power cord and
keep a unit plugged in when I'm working on it (power off, of course).
However, like someone mentioned earlier, this is not the case when I have a
power supply pulled apart.  No power in sight when that's the case -
everything unplugged.  Otherwise, I wear a wrist grounding strap and I
handle all components carefully - e.g. don't touch any lands, circuits,
components, edge connectors unless I have to.  A combination of safety
practices - rather than any one - will keep you and your equipment safe
when you're working on a computer.

I've seen many so called professionals handle electronic components
improperly - apparently uninformed or careless about the dangers of ESD to
sensitive electronic components.  I just cringe when I see this.  They
haven't any idea the damage they could be inflicting on the equipment they
handle.


Joan Rapier
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