[Elecraft] Hidden ESD Dangers (WAS: K3 Technicians.....)

[Ron D'Eau Claire]

The key to being ESD-safe is there being a conductive path between the pins
of any ESD-sensitive part so that all the pins stay at the *same* potential.
That's not always true when the parts are mounted on the pc boards. 

When a part is put into the circuit, normally incidental d-c paths are
provided through the various signal and power circuits so it is now
relatively ESD-safe. 

However, when the board is unplugged from the rig, the circuit paths through
the connector(s) are now broken. Frequently that leaves ESD parts mounted on
the board with open pins that are just as vulnerable as if the individual
parts were being handled separately. 

There are even some circuits in which the pc board circuits do not provide a
d-c path for ESD sensitive parts, even when the board is plugged into the
rig, so that a touch on a certain trace is as dangerous as handling the
loose part. 

Ron AC7AC