What are the Parts of Printed Circuit Boards?

Printed circuit boardsA printed circuit board or may be called as a wire board or wire card is one of the most fundamental parts of an electronic machine or equipment. With this electronic device, the entire machine may function with the help of the electricity that it manufactures. With the connection of the colorful wires, all of which are colored for representation, and all the components on the board, the entire printed circuit board may already run a big machine. A circuit board may look really complex, however, the truth is, there are only few parts on it and some of those are really basic.

It is important to understand the parts of a printed circuit board. It does not need an electrician, technician or engineer to understand these. One must have some basic knowledge about it and all its functions in case there is an emergency or some sort of malfunction in the machineries.

In analyzing the parts of the printed circuit board, it may be noticeable that it looks like cake with lots of layers.To know more about the parts of pcb’s visit www.pcbnet.com.

Circuit boards may come in different layers.

Some are single; some are double while some who have lots of components go as multi-layer. Now, these layers comprise of the different materials used to make a circuit board function. They are actually separated boards laminated together with the help if heat and adhesive.

First is the FR4 or the base material of the board. It is also called as the substrate and is commonly made of fiberglass. With this board or FR4, the entire printed circuit board is rigid and thick enough to hold all the components and the wires intact. The thickness of the board actually depends on the base. Most of the time, the circuit boards are about 1.6mm while some are only .8mm thick boards.

However, cheaper circuit boards or commonly known as perf boards are made of other materials like the epoxies or the phenolics. These boards may be less expensive but it is not as durable as the high-quality FR4. So how does one know if he or she got a poor type of circuit board? The cheap boards smell bad when being soldered and they may be purchased in the low-end electronic shops that sell cheap devices and materials. These boards may be cheaper and friendlier to the pocket but the fact that they use phenolics put everyone’s health on danger as phenolics actually has a low thermal decomposition temperature which may lead to smoke, char and delaminate the board when held too long in the process of soldering.

Another part is the copper which is actually the thin layer of copper foil laminated on the board. The copper is one of the most important parts. When one talks about the layers of the printed circuit board, it is actually the layers of the board. Copper is the one being melted with the help of the soldering paste. Its thickness depends and it is classified in weight specifically in ounces per square foot. Most of the circuit boards have 1 ounce of copper per square foot while some goes for up to 2 or 3 ounce copper. For a more specified measurement of the copper, ounce per square is commonly up to 35 micrometers.

Third part is the soldermask layer or the layer on the top of the copper foil. It is the colored part of the circuit board and is the one which has the traces for the components. With this soldermask layer, the traces are all ensured to be precise. Most of the time, the soldermask follows the color green.

The last part is the white silkscreen that is applied on the soldermask layer. With this, the letters, numbers and the symbols on the circuit board is added. The silkscreen helps in the identification of the components and the wires on the board. Conventional color of the silkscreen is white but other colors may also be used.

The Coins and the Authorities

History narrates the origins of the challenge coins as those that have been started by the military. Its branches have spread out, and some of these coins have been given out by the government, specifically the President of the United States (moving forward – referred to as POTUS), Vice President of the United States (VPOTUS), and the other White House staff.

Brief History

coinsChallenge coins were first introduced by President Bill Clinton, next is President Bush, and after him, President Obama. The first VPOTUS who made the coins was VP Cheney. A small number of these kinds of coins have been created compared to Presidential coins (commemorative, inaugural and tokens) on which thousands have been manufactured.

Both the POTUS and the VPOTUS usually only gave these coins to Military members, to their families, some dignitaries, and to those who have exhibited their support and loyalty to the country in their own ways.

Coins Issued by the POTUS

Here are the coins issued for Barrack Obama:

It has been said that coins given by Barrack Obama are a tough catch. It’s even a treat to see him give one to his men, and witness the encounter end with an electric smile. The stash of coins is carried inside the pants’ left pocket on the front side. A coin is quickly retrieved by the left hand, transferred to the right hand, and then the ‘secret handshake’ starts. Before, the handshake was somehow awkward for Obama, but now the technique is definitely more developed.

He also placed coins on the soldiers’ memorials – soldiers who were killed in the Fort Hood shooting in 2009. He also leaves these coins on fallen US soldiers’ graves to honor their contribution to the country.

Here are the coins issued for George W. Bush:

The former POTUS George W. Bush was said to reserve his stash of challenge coins for those wounded servicemen. He had a small stack of coins with him almost all the time, like those of poker chips on his desk for quick draws. If you see someone who has coins given by George W. Bush, most likely that person got wounded in combat, hence definitely deserving of the coin.
In 2007, during the former POTUS’s short yet unexpected visits, instead of giving a challenge coin, President Bush received one from one of those Marine Control Units. This was in Iraq’s An bar province, specifically in Al-Assad Airbase.

Here are some of the coins issued by Bill Clinton:

Former POTUS Bill Clinton had various racks full of these coins mostly given to him by service members. The racks can be found behind his desk in the Oval Office. The coins are currently displayed inside the Clinton Library.

An Established Custom

The act of handing out these challenge coins is a ritual that has been present in the military for a long time. Aside from the previously displayed presidential coins (which are understandably the ones that are most coveted), lawmakers and high-ranking officials are also said to distribute them.

To add, the POTUS have given these souvenir coins to diplomats and foreign dignitaries as an indication of welcoming and honorary membership.

Already Within Reach

If after all that you’ve witnessed made you want a challenge coin for your own collection, fear no more. It’s not too difficult to have these coins. Again, you don’t have to be a diplomat or a soldier to obtain one.

As previously mentioned, having coins like these no longer need you to take the heroic and/or violent path. You can now easily request and purchase one. These types of souvenir coins are available at stores today.

Have your own challenge coins and show your patriotism and loyalty.

Author Bio:
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