Electronics&Electrical Info.Posted by Lakay Fri, March 13, 2009 15:57:48· How to mprint on a circuit board
· Basic electrical works
· Speaker wiring info.
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· How to mprint on a circuit board
Materials and Supplies
· PhotoEZ™ or StencilPro™
HiRes stencil film
· Liquitex High Viscosity Paint
· Positive image of circuit board design
· Copper clad board
· Ferric Chloride
· Plastic etching tray
This project guide will show you how to make your own printed circuit boards using our silkscreen stencils along with your artwork. It assumes a working knowledge of the process involved in creating the artwork and etching a printed circuit board.
The circuit pattern in this guide is intended only to demonstrate the steps required to make a printed circuit board using PhotoEZ/StencilPro silkscreen stencils. Read all instructions before beginning your project. Read manufacture labels on products and supplies being used. Use safety glasses and gloves when using chemicals. Have FUN!
Project By:
Time to Do: 3-5 hours
Skill Level: Advanced
Step 1: Gather your supplies
Step 2: Create your artwork
The silkscreen stencil is a negative of your circuit design so be sure to layout and print your image as a positive non-mirrored image. For maximum detail use transparence or vellum paper when printing.
Step 3: Make your silkscreen stencil
Expose and develop your film using the original artwork from step
1. Follow the instructions provided with your stencil film of choice. PhotoEZ or StencilPro will work just as well. 
Step 4: Silkscreen etch resist onto your clean copper clad board
Clean and prep your bare copper board as usual. In this example we used an acrylic based paint from Liquitex however any resist that is capable of being silkscreened can be used. Use the following tips to avoid bleeding and pinholes:
o Use plenty of paint.
o Keep squeegee, not lower than 45º angle. This will help prevent bleeding under the stencil.
o Use even strokes and go back and forth only once. Avoid the tendency to paint.
o Lift the stencil slowly. Lifting too fast will create bubbles and possible pinholes
Step 5: Etch your board as usual 
Or.....
You don't need any sophisticated equipment in making a simple PCB.
For a barebones project, you can ink the board using pentel pen, nail-polish, enamel paint by hand drawing it. you might not get straight lines but who really spends time looking at the underside of a circuit?
dip the prepared pcb to the ferric chloride solution and from time to time check the amount of corroded copper.
for an even 'copper less' PCB just get a stiff cardboard, punch in holes to accommodate the ELGS of the components and solder each one together using jumper wires. this technique by the way is employed in emergency situations or in areas that require a flexible PCB, which is really nonexistent.
these are the techniques we did during our classes in electronics.
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· Basic electrical works
Highly advice to check your safety 1st:
1st switch OFF:
Every circuit must be provided with a means of isolation; and you should isolate and lock off before work begins, In order to deter anyone from reconnecting the supply, a danger electrical at work sign should be displayed on the isolation switch. Where a test instrument or voltage indicator such as that shown in fig. Is that the following procedure should be adopted so that the device itself is proved.
1. Connect the test device to the supply which is to be isolated; this should indicate mains voltage.
2. Isolate the supply and observe that the test device now reads 0V.
3. Connect the test device to another source of supply to prove that the device is still working correctly.
4. Lock off the supply and place warning notices, to let other know that electrical works is on going.
5. Used specific and safe protected Electrical tools.
After completing safety test & preparations with 100% safe; then go start with your installation work or electrical works.
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··Basic Electrical Works··
··Basic Electrical Installations··
Electrical source meter Wiring and Lighting circuit:
Recommended that for lighting outlets should assume a current equivalent to a minimum of 100W per lamp-holder. This means that a domestic lighting circuit rated at 5A, a maximum of 11 lighting outlets could be connected to each circuit. In practice, it is usual to divide the fixed lighting outlets into a convenient number of circuits of seven or eight outlets each. In this way the whole installation is not plunged into darkness if one lighting circuit fuses and complies with Regulation which tells us to divide into circuit to minimize inconvenience and avoid danger.
Lighting circuit are usually wired in 1.0 or 1.5mm cable using either a loop-in or joint-box method of installation. The loop-in method is universally employed with conduit installations or when access from above.
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··Lamp & Switch wiring··
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··Speaker Wiring Info··
1.
··Speaker Wiring Info··Series Wiring- For speakers in series you add the impedances of the speakers together. To determine the wattage you add the wattage of the speakers together. If you were using (2) 8 ohm speakers you'd have a 16 ohm cabinet. If you were using (2) 200 watt speakers you'd have 400 watts of power handling.
2.
..Parallel Wiring- Speakers of equal impedances you divide the impedance value by the number of speakers. To determine the wattage you add the wattage of the speakers together. If you wire (4) 16 ohm speakers in parallel you'd have a 4 ohm cabinet. (2) 16 ohm speakers in parallel would give you an 8 ohm cabinet.If you were using (4) 100 watts speakers you'd have 400 watts power handling. If you were using (2) 100 watt speakers you'd have 200 watts power handling.
3.
..Series/Parallel Wiring- All speaker's should be the same impedance & wattage. The impedance of the cabinet will be the same as one speaker. The wattage will be 4 times the individual speaker wattage. If you're using 8 ohm speakers the cabinet will be 8 ohms.If you were using 100 watt speakers the wattage for the cabinet will be 400 watts power handling.
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Continue Reading More Tutorial Here!
Computer TutorialPosted by Lakay Fri, March 13, 2009 15:27:17· Instructions how to assemble your own PC
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PREPARE THE CASE
STEP 1: Preparing the Case
Outside case
Inside Case
PREPARE THE CASE
The Computer Case houses all the computer components. The first step is to slide the side panel off the case. Most side panels are secured by several screws. Inside the case are various regions that perform different functions.
The Power Supply which will typically come installed in the computer case supplies power to the computer via various sized Power Connectors and one larger ATX Power Connector.
The Motherboard Pan keeps the Motherboard in place using Brass standoffs or plastic connectors.
The Full-Height Drive Bay holds the computers CD-ROM, DVD, and CDRW drives. When these devices are installed the plastic plate on the outside of the computer case is snapped out to allow the computer user access to these devices.
The Half-Height Drive Bay contains the computers Floppy Drive, Hard Drive, as well as any other Half-Height devices E.G. Zip drive.
The PC Speaker issues various noises that give audio cues to the inner workings of the computer. For example when the computer first boots up, it emits a beep after successfully completing its self-test.
Your Computer case should come with a little bag filled with screws.
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Chassis screws- These are little screws that are used to hold your computer cards in place.
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Motherboard screws- These are used to fasten the Motherboard to the Motherboard pan.
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Standoffs-These are either Brass or Plastic and are used to hold the Motherboard firmly in the case while at the same time keeping it from touching the actual metal case, which could cause a short in the motherboard.
Make sure you set the power supply to the proper voltage. 110v in the United States and 220v in other parts of the world.
You might have to install the little plastic feet on the bottom of your computer case. If you do, do it now.
STEP 2: Preparing the mother board
GETTING STARTED
Your Motherboard is the backbone of your computer. It connects your peripherals into one cohesive unit called computer.
Before you actually install the Motherboard, you should first configure it. This is where purchasing a Motherboard with a coherent manual comes into play. The Manual will instruct you how to configure your Motherboard so that it will work with your CPU. This is accomplished by setting various jumpers and dip switches. A Jumper is a set of two or three pins that jut out from your Motherboard. They are set by either capping or uncapping them with a little rubber cap. If they are uncapped then they are considered off, if they are capped then they are considered on. Your manual will tell you which jumper needs to be capped, based on what type of CPU you are using. There are some newer Motherboards that are completely "Jumperless" and are configured in the BIOS, with a special CMOS, program.
PREPARING THE MOTHERBOARD
Here is the basic procedure:
Each Motherboard has different configuration methods, so make sure to read the manual.
Set the voltage settings.
Set the jumpers to match the voltage for your CPU. Your manual should have a guide as to what your CPUs voltage should be or just read it from the chip itself.
Some boards are designed to detect the voltage automatically and then use the correct voltage. In this case, you will not have to worry about it.
You also have to configure your Motherboard so that it matches your Processor speed, and the Bus it was designed to work with. You tell the Motherboard about the processor through a roundabout way.You set the CPU speed by using a "multiplier" which is a number that when multiplied by the Bus speed equals the CPU speed. For example, if you have a CPU that was designed to work at 800MHz on a 100MHz bus, you would first set the Motherboard bus speed to 100MHz and would then tell the motherboard you are using an 800MHz CPU by setting what is called a multiplier to a setting of 8.0.
If your manual lists settings by CPU, just do what it says.
THE LAST STEP
The last step to configuring your Motherboard is to make sure all the default settings are correct. This involves going through the manual and all the default dip and jumper settings match the ones on your motherboard.
For Next Steps....
Step 3: Installing the CPU
Step 4: Installing the Memory
Step 5: Installing the Motherboard
Step 6: Installing the Floppy Drive
Step 7: Preparing and Installing the Hard Drive and CD-ROM
Step 8: Installing the Video Card, Sound Card and Modem
Step 9: Booting Up
Step 10 :Finishing Touches
Continue reading more tutorial here!
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