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PCB OR a printed circuit board is a component made out of layers of insulating materials with electrical conductors. The insulator can be made of many materials mainly plastic, fibreglass and ceramics. During manufacture , the extra conductors that are not required are etched off, leaving printed circuit made of those required conductors where we can attach our electronic components .

Now obviously this is a very fancy definition , for a layman PCB is nothing but a normal board like your veroboard where the circuit patterns are already printed with the help of conductors like copper so that you do not need to attach any more wires to the circuit.
Now that we know what a pcb is , another question comes why the hell we need pcb's??

The answer to that question is given by the following points:

1. The first reason can be , a pcb can give much higher density in the circuit connection that it has.
2. They easily reduce the number of wiring errors that we can make in a normal veroboard as the circuits are pre-made and the design is embedded into the pcb.
3. They can really decrease assembly cost over a long period of time .
4. They consume less space than the traditional circuit board because the etching and the circuits are made by the use of chemicals and not hand.
5. The circuits are much more reliable than traditional circuit boards as minimal no. of wires are used hence a smaller chance of the circuit falling apart due to some kind of loose connections.

These are some of the basic advantages of a pcb over a normal circuit board , enough reasons to make us motivate to make our own pcb's than relying on unreliable veroboards.

Now the discussion goes into the more practical part of the tutorial i.e What materials are needed and how to make a PCB.

MATERIALS REQUIRED:

1. ETCHING MATERIAL EITHER FERRIC CHLORIDE OR AMMONIUM PERSULPHATE , JUST FOLLOW THE GIVEN INSTRUCTIONS FOR DILUTION LEVEL.
2. PLASTIC TRAYS OR CONTAINERS FOR THE CHEMICALS(DONT USE METAL).
3. COPPER CLAD BOARDS.
4. A LASER PRINTER (FOR THE TONER TRANSFER) (If you don't have a laser printer, then you can take a photocopy of your printout).
5. A DRILL PRESS.
6. BASIC TOOLS SUCH AS HACKSAWS, A FILE, SANDPAPER OR SCROTCH BRITE
7. SMALL DRILL BITS.
8. SEMI GLOSS PAPER(INCREASES CLARITY OF THE CIRCUIT PATTERN).

PROCEDURE:

1. The 1st thing to do is to make the PCB layout either by using the eagle cad or by using EXPRESSPCB software...these software are easily available and tutorials are available to help u make such a layout......
2. Now take a printout of the layout in a semi gloss paper.

   

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3. Now take the printout and cut out the design ... place this Design on the copper clad board ..face down..Take a heating iron and heat the paper along with the board so that the paper is completely stuck with the board...give good pressure and leave no gaps...

   

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4. Take this board with the design stuck to it and soak it in soap water for some time so that the paper becomes soft and can be easily removed

   

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5. Then CAREFULLY remove the paper. Be sure not to remove any of the black ink traces because these are what stops the acid in the etching process. Use a kind of rubbing motion to remove the paper. Keep it wet all the time so that it separates easily from the copper board.

   

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6. The pcb is done and ready for etching now....use an etchant and follow the normal dilution level given...use a glass or a ceramic bowl...do not use copper or iron bowls.

   

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7. Dilute the etchant with boiling water and place the pcb inside it..And slowly swirl or rock the bowl around. The liquid must be always moving over the copper board to get it to etch properly.

   

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8. Now remove after all the copper has been etched and scrub the blank ink off the board and there u have UR NEW PCB BOARD...

   

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9. Use drill bits to make holes whereever required in the pcb and attach ur components to it....

   

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Courtesy of SocietyOfRobots

Cool Regi... another great one

Find a good PCB design software at https://robot.lk/viewtopic.php?f=63&t=2100

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