Hi Deepak, To answer your first question, the 2kV high voltage rating on the capacitor is for protection from ESD/surge type events and it has no effect on radiated emissions. You saw worse results with a 0 Ohm resistor than solder probably due to the higher inductance (ESL and mounting inductance) of the 0 ohm resistor. Thanks, Ram Chundru EMC Engineer Apple Inc. ________________________________ From: deepak Engineer <deepaksiengg@xxxxxxxxx> To: si-list@xxxxxxxxxxxxx Sent: Wed, September 22, 2010 8:27:22 AM Subject: [SI-LIST] Re: è?ªå?¨å??å¤?: Emission Problem with Ethernet Hello Experts, To control the Emmision from Ethernt port, now I am using a two seprate ground. My question is: 1. How 1nf, 10v and 1nf,2kv will make a difference in EMI test. I had only 1nf, 10V smd capacitor available, but it gives 4bd spike above the margin. do you think that for Emission test the voltage rating is important? I though it will improve the emission transition but not making any difference. 2. Similarly if I try a 0ohms then I am getting better result compare to capcitor...below the margin -1.88db but if I am shorting the two plane with solder then again I am getting a 2db spike above the margin. here what are the advantage of 0ohms vs solder..?? what is the best option, 1nf or 0ohms or solder ? what will help for ESD protestion? from previous discussion of Daniel, I can see 1nf as a solution, but pratically 0ohms is giving a better result. thanks in advance, Deepak 2010/9/18 <aub4362@xxxxxxxx> > æ?¨å¥½ï¼?æ??å·²æ?¶å?°æ?¨ç??æ?¥ä¿¡ã?? > æ??ç?°å?¨å¤?å?ºä¸ï¼?å½?è¿?å??å??ä¼?å??æ?¶ç»?æ?¨å??å¤?ã?? > 谢谢ï¼? > > ------------------------------------------------------------------ To unsubscribe from si-list: si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field or to administer your membership from a web page, go to: //www.freelists.org/webpage/si-list For help: si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field List technical documents are available at: http://www.si-list.net List archives are viewable at: //www.freelists.org/archives/si-list Old (prior to June 6, 2001) list archives are viewable at: http://www.qsl.net/wb6tpu ------------------------------------------------------------------ To unsubscribe from si-list: si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field or to administer your membership from a web page, go to: //www.freelists.org/webpage/si-list For help: si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field List technical documents are available at: http://www.si-list.net List archives are viewable at: //www.freelists.org/archives/si-list Old (prior to June 6, 2001) list archives are viewable at: http://www.qsl.net/wb6tpu