Via holes (vias) are provide in a PCB for taking signal traces from one layer to another. So all multi layer PCBs will have via holes. Vias are also provided for supporting and assembling through hole devices or connectors.
You'll need a design, which you'll transfer onto a circuit board "blank" which has copper foil covering it completely (one side, or, maybe, two). With the design transferred to the board, you'll coat it with an etch-resistant material. The "resist" will cover the circuit pathways you want to keep, and the etch will remove the rest of the copper. Etching done, rinse, and then apply a solvent to remove the "resist" and expose the copper. That should be your board. You will have to drill holes in it if you go with through-hole components rather than surface mount. There are some video clips on YouTube on this subject. You'll find a link below. Be careful with the chemicals! They can be nasty! Please! Use, store and dispose of them properly. Thanks.
The holes on the back are there for quick wiring. You strip the wire and then insert it into the holes. It is held in place by spring tension. I do not recommend you wire the outlet by using these holes. From my experience the wires are not secure enough. Strip the wire and wrap it around the screws and tighten it securely which is what all the good electricians I know do. Takes a little longer but IMO it is more secure.
To over come creeping effect on no-load, 2 holes are drilled on the opposite sides of the spindle. This causes sufficient distortion of the field to prevent rotation when one of the holes comes under one of the poles of the shunt magnet. Courtesy - Industrial Instrumentation and Control
Holes and electrons
Electrons constitute electronic current in n-type substance and holes constitute conventional current in p-type substance.The motion of electron in a n-type substance is opposite to that of holes in a p-type substance.
A printed circuit board is basically used to mechanically support while at the same time electrically connecting electronic components by using conductive pathways. The process is very simple.motherboard is a printed circuit ,where all components of the system is connected.Printed circuit boards are used in nearly all electronic devices.The conducting wires that connect all the components, are printed onto an insulating plastic material such as paxolin or fiberglass. These tracks are commonly made of thin copper sheet stuck to the board. The tracks are then printed using light and a chemical process to remove the unwanted copper.Some boards used in remote controls and wafer thin boards used in ipods etc, are commonly printed, using conductive ink containing silver or carbon.The alternative to printed circuits was to idividually wire the coponents using wire and solder tags. Old tube radios were originally wired this way, but had to be made by hand.Printed circuits allow for automation and mass soldering using a float soldering process on a bed of molten solder.
Most radios begin with a printed circuit board- metallic copper printed onto a fiberglass board- this will be most of the wiring. A computer controlled machine "stuffs" the holes in the circuit board with transistors, capacitors and resistors, and they are all soldered in place at one time.
Strip boards are used to create prototype electronic circuits without soldering. Components are inserted into holes on the board and their leads are bent to make contact with the conductive strips running along the board. This allows for temporary testing and validation of circuit designs before final assembly.
Relief holes are provided for easy handling of sine bar and for reducing the weight of the sine bar.
To effectively screw two boards together side by side, align the boards evenly and use a drill to create pilot holes through both boards. Then, insert screws into the pilot holes and tighten them with a screwdriver or drill to securely join the boards together. Make sure to use screws that are long enough to penetrate both boards but not too long that they come out the other side.
Surface-mount technology (SMT) is a method for constructing electronic circuits in which the components are mounted directly onto the surface of printed circuit boards (PCBs). An electronic device so made is called a surface-mount device (SMD). In the industry it has largely replaced the through-hole technology construction method of fitting components with wire leads into holes in the circuit board. Both technologies can be used on the same board for components not suited to surface mounting such as transformers and heat-sinked power semiconductors.
To reduce the weight
Two types of mounting are surface mounting, which involves placing components directly onto a printed circuit board, and through-hole mounting, which involves components being inserted through holes on the board and soldered in place.
#2 lumber is the low end 1x boards. They will have knot holes and splits.
Relief holes are provided for easy handling of sine bar and for reducing the weight of the sine bar.
To replace deck boards effectively and efficiently, follow these steps: Remove the old boards carefully using a pry bar or screwdriver. Measure and cut the new boards to fit the deck. Pre-drill holes for screws to prevent splitting. Secure the new boards in place with screws or nails. Seal or stain the new boards for protection.
Traditionally cribbage boards are made from wood with a series of holes of drilled though them. Usually they are made from a type of hard wood material like oak.