I came to listen an inspring speech titled “The fringe benefits of failure” deliverd to Harvard Graduates by JK Rowling.The speech starts rather humorously mentions about her early life,poverty, fear of failure & memories at Amnesty.She winds up by quoting Seneca -“As is a tale, so is life. It is not how long it is, but how good it is, that matters.”

Stiching (Fencing) Vias how they affect the system performance?

http://www.millertechinc.com/pdf_files/MTI%20TN1014%20Stitch%20Vias.htm

Right Angle Micro Strip Lines-Do they cause problems?

http://www.millertechinc.com/pdf_files/MTI%20TN063%20Microstrip%20Right%20Angle%20Bends.htm

Some Good RF Layout Practices from Maxim Application Note.

http://www.maxim-ic.com/app-notes/index.mvp/id/4636

I do like history & always liked to read historical articles. Recently i was caught upon reading the history of christianity in India & came across a lots facts that i was previously unaware of.But i can assure you all these things are of little use or of no interest to anyone other than a pure historian or a person who is too inclined to the subject.

The good thing about the history ( or bad thing ?) it usually reflects the likeness or belief about the incidents, of a person who writes it ,either purposefully or accidently.So most history books needs to be approached with a critical mind but not with some unquestionable authority.

Some interesting facts i ve came across while reading the web links im posting here…

India has been in the early centuries been in association with the Church of East & both traces origin to Saint Thomas Apostle…wikipedia says

“Between the 9th and 14th centuries Church of East was the world’s largest Christian church in terms of geographical extent, with dioceses stretching from the Mediterranean to China and India”.

History of Indian church is closely associated with this ancient church & is never complete without it, though most historians neglect it.

Nevertheless Malabar christians were part of the Church of East till the advent of  Portuguese in 16th century.There after geo-political reasons and external forces caused the Chuch in India to split. At about the same time also the Church of East also under went schism &  persecution and one faction entered into communion with Catholic church,the other which remained is now known as Assyrian Church of the East, ruled by Catholicos-Patriarch Mar Dinkha.

Reading about this church is very touching since it has been persecuted & tortured most during its life time.The  original seat of patriarch Qodshanes in Hakkari is inaccesible to the church & the primates still lives in exile..

You can read about the Qodshanes in Hakkari & History & heroism of this very old church at below links.

The Nestorian Vatican of the Assyrian tribes

http://www.shlama.be/shlama/content/view/213/179/

http://www.shlama.be/shlama/content/view/212/178/

Who are Assyrians?

http://www.everyculture.com/Africa-Middle-East/Assyrians.html

The time spent on the pad (by a soldering iron during soldering) is called “dwell time.”

When components are soldered on the PCB pads say a two terminal component to a footprint containing two pads,May be one of the pad resides in a ground plane while other is attached to a signal trace , when automated soldering process the ground plane pad will act as a good thermal conductor and sinks more heat and cools faster.This brings about uneven cooling time and may cause bad joints.to avoid that and to increase the dwell time,the copper around the pad residing in the ground plane is removed.

IPC2221 Section 9.1.3 says,

“Thermal Relief in Conductor Planes Thermal relief is only required for holes that are subject to soldering in large conductor areas (ground planes, voltage planes,thermal planes, etc.). Relief is required to reduce soldering dwell time by providing thermal resistance during the sol-
dering process.”

I recently had the chance to read an old interview published in EDN magazine & had the oppurtunity to learn about the innovators who worked behind the great PCB Layout Tool Orcad had  been offering till recently.Earlier in 1995 Orcad had the best schematic tool but lacked a good PCB Layout Tool.So they bought the comapnay called Massteck which had already developed an excellent PCB Layout tool with great auto routing capability that achieved even 100% routing.Ken Wadland & Chuck Grant were two important people who worked behind the Massteck PCB Layout Tool

The full interview is available at the following link.

http://www.edn.com/article/458682-Improving_on_PCB_design.php