Hi Lee and the group,
I am not assuming but have measured the effect. I have measured for myself just
about every engineering principle I have come across starting with duplicating
one of Marconi's radio experiments when I was 11 years old studying electronics
(it worked). I guess I am a lab rat!
If you like we could have a GoToMeeting session and I can show you my experiment
and data to make sure we are thinking of the same effect.
I am in Miami Beach for a board meeting of an EMC tech company and will be home
late Wednesday. Let me know a time convenient for you. My test board models
either a 4 layer board or an "n" layer board where I am just concerned with the
top and bottom two layers.
Doug Smith Sent from my iPhone IPhone: 408-858-4528 [tel:408-858-4528] Office:
702-570-6108 [tel:702-570-6108] Email: doug@xxxxxxxxxx Website:
http://dsmith.org
On Sat, Nov 7, 2015 at 13:13, Lee Ritchey <leeritchey@xxxxxxxxxxxxx> wrote:
Doug,
The assumption you are making when you do this is that emissions will get worse
if you don't do this. Is that true?
-----Original Message-----
From: si-list-bounce@xxxxxxxxxxxxx [mailto:si-list-bounce@xxxxxxxxxxxxx] On
Behalf Of Douglas Smith
Sent: Saturday, November 7, 2015 5:27 AM
To: Lee Ritchey <leeritchey@xxxxxxxxxxxxx>
Cc: chris.cheng@xxxxxxx; Scott McMorrow <scott@xxxxxxxxxxxxx>; Shimko, Steve
(ES\) <s.shimko@xxxxxxx>; istvan.novak@xxxxxxxxxxx; dmarc-noreply@xxxxxxxxxxxxx;
si-list@xxxxxxxxxxxxx; bbakshan@xxxxxxxxx; Kevin.Hou@xxxxxxxxxx
Subject: [SI-LIST] Re: EXT :Re: What's the purpose of stitching vias whichjust
connect one GND layer?
Just to be clear, I was speaking of single or a few vias at places where a
signal changes many layers on a PCB, not for crosstalk control. The purpose is
to keep down emissions or increase immunity on a PCB.
Doug Smith Sent from my iPhone IPhone: 408-858-4528 [tel:408-858-4528] Office:
702-570-6108 [tel:702-570-6108] Email: doug@xxxxxxxxxx Website:
http://dsmith.org
On Fri, Nov 6, 2015 at 19:08, Lee Ritchey <leeritchey@xxxxxxxxxxxxx> wrote:
Chris,
Well put!
-----Original Message-----
From: si-list-bounce@xxxxxxxxxxxxx [mailto:si-list-bounce@xxxxxxxxxxxxx] On
Behalf Of Cheng, Chris
Sent: Thursday, November 5, 2015 12:51 PM
To: doug@xxxxxxxxxx; Scott McMorrow <scott@xxxxxxxxxxxxx>; Shimko, Steve (ES)
<s.shimko@xxxxxxx>
Cc: Lee Ritchey <leeritchey@xxxxxxxxxxxxx>; istvan.novak@xxxxxxxxxxx;
dmarc-noreply@xxxxxxxxxxxxx; si-list@xxxxxxxxxxxxx; bbakshan@xxxxxxxxx;
Kevin.Hou@xxxxxxxxxx
Subject: [SI-LIST] Re: EXT :Re: What's the purpose of stitching vias whichjust
connect one GND layer?
Must have VIAs------Steve
No VIAs for you ------ Lee
Chris Cheng
Distinguished Technologist , Electrical
Hewlett-Packard Enterprise Company
+1 510 344 4439/ Tel
chris.cheng@xxxxxxx / Email
4209 Technology Dr
Fremont, CA 94538
USA
-----Original Message-----
From: si-list-bounce@xxxxxxxxxxxxx [mailto:si-list-bounce@xxxxxxxxxxxxx] On
Behalf Of Doug Smith
Sent: Thursday, November 05, 2015 11:58 AM
To: Scott McMorrow; Shimko, Steve (ES)
Cc: Lee Ritchey; istvan.novak@xxxxxxxxxxx; dmarc-noreply@xxxxxxxxxxxxx;
si-list@xxxxxxxxxxxxx; bbakshan@xxxxxxxxx; Kevin.Hou@xxxxxxxxxx
Subject: [SI-LIST] Re: EXT :Re: What's the purpose of stitching vias whichjust
connect one GND layer?
Can someone translate the characters below for me?
Doug
University of Oxford
Department for Continuing Education
Oxford, Oxfordshire, United Kingdom
--------------------------------------------------
Doug Smith
P.O. Box 60941
Boulder City, NV 89006-0941
TEL/FAX: 702-570-6108/570-6013
Mobile: 408-858-4528
Email: doug@xxxxxxxxxx
Web: http://www.dsmith.org
--------------------------------------------------
On Thu, 5 Nov 2015 19:45:03 +0000, "Shimko, Steve (ES)"
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