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Message-ID:	<4FBE8123.2090205@laserlinc.com>
Date:	Thu, 24 May 2012 14:42:43 -0400
From:	Joshua Lansford <Joshua DOT Lansford AT laserlinc DOT com>
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To:	geda-user AT delorie DOT com
Subject:	Re: [geda-user] Chassis ground vs Circuit ground
References:	<4FBE499D DOT 2090509 AT laserlinc DOT com> <CAN0Jx-9co9=9cU9aGfKdyhmjQC3je+n-3z0vFM+4xYDiCGvcoQ AT mail DOT gmail DOT com>
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Reply-To:	geda-user AT delorie DOT com

Sounds like the edges shouldn't be plated as they would form new 
"drawbridges" in addition to the power supply header.
(http://www.sigcon.com/Pubs/news/7_02.htm)
The second link suggests the edges be grounded to shunt current.  But 
this is only recommended if the inputs must reference chassis ground 
which mine are not.
(http://www.sigcon.com/Pubs/edn/multipleadc.htm)

But without sensitive analog signals to protect besides the Ethernet 
signal I am probably good any which way I go.  I am just trying to learn 
best practice.

Thank you Russell.
That was informative.
~Joshua

On 05/24/2012 11:26 AM, Russell Dill wrote:
> On Thu, May 24, 2012 at 7:45 AM, Joshua Lansford
> <Joshua DOT Lansford AT laserlinc DOT com>  wrote:
>> Hello.
>>    I have an Ethernet Jack with a separate chassis ground.  The grounds
>> connect by zero ohm resistors beside the jack.  Supposedly this keeps noise
>> from following the cable onto board.  I saw somewhere not connect chassis
>> and  together on the board but though the enclosure.  The card with plated
>> edges slides into a metal extrusion.  Should both edges be chassis ground or
>> should one be circuit ground?   This supposedly keeps a DC difference from
>> developing but dissipates noise.  What are your opinions about how to deal
>> with chassis ground vs circuit ground?
>> ~Joshua
> http://www.sigcon.com/Pubs/news/7_02.htm
> http://www.sigcon.com/Pubs/edn/multipleadc.htm
> http://www.sigcon.com/Pubs/news/2_17.htm
>
>

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