Looks like the only solution is to work under water. All of the
voltages exceed the 30 volts or so level we have heard cause damage
to sensitive components.
73
Rick Dettinger K7MW
====================================
On Jul 26, 2008, at 9:51 AM, Ron D'Eau Claire wrote:
This is a subject that comes up here regularly among those working on
their Elecraft (and other) rigs.
Doing some research on a project, I ran across the following values
published by Hewlett-Packard Company. They provide some insight about
why it's important to use ESD-safe handling procedures.
The "PCBs" mentioned below are, of course, Printed Circuit Boards, not
the stuff found in old capacitors and transformers. "DIPs" are Dual
In-line Pin integrated circuits such as found throughout Elecraft
rigs.
Typical Electrostatic Voltage Levels
Relative Humidity for each voltage level shown below:
10%
40%
55%
Walking across carpet
35,000 V
15,000 V
7,500 V
Walking across vinyl floor
12,000 V
5,000 V
3,000 V
Motions of bench worker
6,000 V
800 V
400 V
Removing DIPS from plastic tube
2,000 V
700 V
400 V
Removing DIPS from vinyl tray
11,500 V
4,000 V
2,000 V
Removing DIPS from Styrofoam
14,500 V
5,000 V
3,500 V
Removing bubble pack from PCB
26,500 V
20,000 V
7,000 V
Packing PCBs in foam-lined box
21,000 V
11,000 V
5,000 V
Ron AC7AC
_______________________________________________
Elecraft mailing list
Post to: Elecraft@mailman.qth.net
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/subscribers.htm
Elecraft web page: http://www.elecraft.com
_______________________________________________
Elecraft mailing list
Post to: Elecraft@mailman.qth.net
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/subscribers.htm
Elecraft web page: http://www.elecraft.com
