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From: agengcc@unx2.ucc.okstate.edu (Gordon Couger)
Newsgroups: sci.electronics
Subject: Re: room shielding
Message-ID: <1991Apr13.061524.12303@unx2.ucc.okstate.edu>
Date: 13 Apr 91 06:15:24 GMT
References: <970028@hpdmd48.boi.hp.com> <1991Apr13.031643.3772@world.std.com>
Organization: Oklahoma State University Computer Center
Lines: 58

In article <1991Apr13.031643.3772@world.std.com> digex@world.std.com (doug e humphrey) writes:
>
>I am building out a computer room in my basement, to hold all of 
>the fun machines that are sitting around running and producing 
>bad EMI.  Not a real problem before, but now I am getting into
(stuff deleted)

I would start by getting some thin sheet iron (not galvinized zink 

fumes will kill you) cut them out to fit floor walls and ceiling and 
solder all the joints. Cover the windows with hail screen and
electricaly connect it to the walls. Doors should be plated with

steel and connected to the sheild. All power lines should be in
conduit properly grounded. Ideally the computer room should have its own
electrical service on a seperate transformer. Ferrite chokes and rf
opto-isolation of all rs232 lines and parallel would be nice. The lines
should be carried in conduit grounded only at the computer end. I would
think that isolation of the computer ground and the radio ground would
be very helpful.

This is best performed on the third day of the new moon accompanied by
the sacrifice of an administrator, an elected official or a any number
of lawyers. 
Battery powered computers seem to cause me less trouble in the shack. 

Gordon
agengcc@unx2.ucc.okstate.edu (Gordon Couger)

D
the sacrifice of an admistrator or 
the sacrifice 

opto-isolation 
bypass capacitors across the AC at every outlet. Opto isolation 
conduent
 





>
B
A
B
B

>since I want to get this done fairly quickly) and places to obtain
>materials would be welcomed.  Ways to cover the power lines and
>phone lines coming in, and of course the data lines going out of
>the room would be useful too, etc.
>
>Thanks.  Hope this is a fun discussion for all of you too!
>
>Doug Humphrey
>Digital Express Group
>Crypto Systems Division (this week...)