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To all electronic, robotic or PIC micro controller geeks out there, if you are reading this, I need a favor from you.

I realized that there are many community and forum out there that discuss on D.I.Y. electronic and embedded system projects. Yet, some students and hobbyists still find it quite hard to get what they want to be done, or maybe something that can really satisfy their needs.

If you are one of them, here’s a favor I need from you. If there is such a blog or forum out there doing discussion on such topics, I mean topics on any projects involving PIC micro controller, what would you expect from it? I mean how would you like a blog like that to exist in order to help you in whatever PIC micro controller projects you are working on, be it for competition, for final year project, for fun, or for whatever reason you want it to be.

For those who are interested, kindly let me know how you think bout this idea by posting it in my comment box.

Thank you.

Working with lab power supply is very common for engineering students as we need it to power up whatever project we are working on. However, there are times when we are unable to access the lab, and buying a lab power supply for personal usage might cost a bomb. Hence, I’ve come up with a much cheaper solution, which is to make a power supply unit from discarded computer (desktop) ATX power supply. With less than RM50 and a little modification, I can get a power supply unit with short circuit protection, high output current and highly regulated output voltage.

How can you do it as well? Read on…

Step 1:

Unplug the power cords at the back of your unwanted CPU, open the CPU casing and locate the power supply (normally a gray color metal casing box). Trace and disconnect all the wires connecting from the power supply to the devices and boards. Remove the power supply unit from the CPU casing.

Step 2:

You will need some extra components to convert this power supply into a usable unit.

1. Heat shrinkable tube (to protect unwanted conducting part).
2. A current limiting resistor, typically 330 ohm ¼ Watt (470 ohm may do as well).
3. A power resistor, typically 10 ohm 10 Watt (or greater).
4. An LED.
5. A toggle switch (to turn the power supply ON and OFF).
6. Audio socket/connector (actually any suitable socket/ connector can do).

If you are using audio socket/connectors, you may label each of the sockets with the respective output voltages using liquid marker.

Step 3:

If you are using a power supply from discarded computer, it is advisable to discharge it by letting it sit unconnected for a few days. However if you are using a new unused ATX power supply, you may straightaway proceed to the following.

Remove the screws locking the power supply with its cover. You’ll probably have a power supply similar to below:

Notice there is a bundle of long wires with different colors soldered to the board of the power supply. Each color represents different voltage level:

- Black = 0V (Ground)

- Red = +5V

- White = -5V (some power supply do not have this voltage)

- Yellow = +12V

- Blue = -12V

- Orange = +3.3V

- Purple = +5V for standby (normally not used)

- Gray = Power ON (output)

- Green = Turn DC ON (input)

Cut off these wires, but make sure you LEAVE A FEW INCHES for future use. Bundle the wire of same color together.

Step 4:

Here comes the hard part. You’ll need to drill holes on the casing of the power supply to mount the audio socket/connectors, LED and toggle switch.

1. Measure and mark the area to be drilled with a tap and hammer.

2. Use drill bit of appropriate size for component mounting.

3. Remember to drill holes for mounting LED and toggle switch as well.

There is no standard way to go around, just make sure you do this carefully and do not break the casing.

Step 5:

Mount and screw the audio socket/connectors to their respective holes on the casing. Next, connect all parts together as follow:

1. Connect one of the red wires to one of the power resistor’s lead, and the remaining to the socket labeled +5V.
2. Connect one of the black wires to the other lead of the power resistor, one black wire to a 330 ohm (or 470 ohm) resistor attached to the cathode of the LED, one black wire to the common terminal of the toggle switch, and all the remaining black wires to the socket labeled 0V.
3. Connect the yellow wires to the +12V socket, the blue to -12V socket, the grey to the anode of the LED, and the white (if your power supply have any) to the -5V socket.
4. Connect the green wire to the normally opened (NO) terminal of the Toggle Switch.
5. Some power supplies may have either a gray or brown wire representing power good. Connect this wire with one of the orange (+3.3V) wires; if not your power supply will not work.
6. Finally, make sure all soldered connections are insulated with the heat shrinkable tube and organize the wires accordingly. Mount the LED and toggle switch to their respective holes. If possible, fix the power resistor to the heat sink of the power supply.
7. Make sure there is no short circuit connection (beware that the casing of the power supply can conduct electricity). Cover and screw the casing back to the power supply unit.

There you go, a self-modified power supply unit for your project.

Works pretty well with my project

Please bear in mind that there are a few precautions you need to know:

1. This modified computer power supply is suitable for testing purposes and powering simple circuit, but its performance can never match a good lab power supply. Hence, if you intend to do more than just testing, it is more advisable to get yourself a lab power supply.
2. Line voltage can kill, so be extra careful when dealing with the supply power unit.
3. Make sure no metal dust fall into the circuit board of the power supply when drilling.
4. The power resistor is used to dissipate power when the power supply unit is not connected to any load. Hence it will get hot if the unit is turn ON. A good suggestion is to mount it onto the heat sink of the power supply.

Mounting power resistor onto heat sink

Hope this DIY information is useful to you. Have fun…

My second trip to Penang for industrial training.

The last trip was mainly on technical works.

This time, we’re given the opportunity to get our hands on another aspect in the engineering field: sales and marketing.

NEPCON is basically an industrial electronic and automation exhibition. It is an effective way for suppliers to launch their new products and services to buyers, grow new businesses and gain new contacts.

Some sort like PC Fair la, except they’re selling larger guns machines and tools.

This is the second year Vanguard Electronic (the company I’m attached with) participated in the exhibition. Last year’s response was not very satisfying (according to one of my seniors la…), but this year seems to be better, despite the economy downturn.

One of our company’s products, almost cost a proton perdana

“Sales engineer” in action =P

The exhibition took 3 days and all of us was so exhausted, standing in the booth from 9am til 6pm everyday. Nonetheless, it was a great experience for us to get to know the market, industrial profiles and those “big boys with big toys” in the industry.

Farewell dinner

My lecturer once told us that as an engineer, we’d ended up dealing with only 2 types of thing: the dead (machines) and the alive (humans). Knowing our own strength and which of those is the best for us is crucial in determining our future.

Now I’ve been exposed to both, but I’m yet to decide which is best for me. The future still seems so blur…

The past three days have been very busy, as I followed the company to the North Peninsular of Malaysia to conduct my training. Finally… something interesting for my internship. =P

On Thursday, our first station was Politeknik Sultan Abdul Halim Mu’adzam Shah (POLIMAS), Penang. Their “Rota Spray” machine was reported faulty, but after some checking, it’s just some pipes that were stuck, causing the sensor unable to work properly.

The second station was Politeknik Tuanku Syed Sirajuddin, Perlis. The campus is quite new and the environment is good (well, at least better than my own uni …). We didn’t stay long there as we’re just dropping by to return their after-serviced “Rota Spray” machine.

The third station of the day was Faculty of Engineering of Universiti Sains Malaysia (USM), Nibong Tebal. The environment is even better than the previous polytechnic!

Didn’t managed to get any photos of the campus, but what I can say is their lab is way better than many local universities. It’s small but fully equipped with updated industrial PCB machines and they produced high quality boards.

On Friday, the second day of our trip, we proceeded to Universiti Teknologi Mara (UiTM) Seberang Prai Campus to discuss with their technician regarding reallocation of their PCB machines in their electronic lab.

This, ladies and gentlemen, is another lab that is comparable to USM’s. They as well have all the necessary machines for producing fine PCBs, and their technician is very concerned and updated with the progress of other universities regarding lab improvement matters.

Our last station was Asian Institute of Medicine Science and Technology (AIMST) University, Sungai Petani. This is something like the Indian version of UTAR actually; with majority of their students are Indians. And the campus environment, what I can say is… fantastic! Especially their buildings.

They’ve recently bought some machines and equipments from our company and we’re here to conduct a seminar to teach the lecturers and students on the proper way of using those machines to produce PCBs.

Ya most of you’ll probably say “PCB again?!”. Well not my fault la pals, the company I’m attached to is dealing with this type of business. =P

Since my boss can hardly spare time to train us, he decided to take us along to train together with AIMST’s lecturers and students.

Got the chance to get my hands hot.

The trip was really worth it (since the company bear all our expenses… =P). Many of the universities and even polytechnics are advancing to become better. Unfortunately, I didn’t see anything alike going on in my uni. We’ve been stuck in old technologies for so long and yet, the uni doesn’t seems to care about it. Something is wrong…

Reached KL at 12am last night, and I’m back to work today.

After more than a week back in UTM struggling to complete my task, there’re 3 things I’m totally positive:

First, automatic is not always the best option, manual can do better.

Second, after years of learning electronics, I sucks…

Third, I’m lacking of sleep and I miss my bed…

As usual, this holiday I’m staying back in UTM while most of my friends are enjoying their happy holiday.

This time I’m in charge of the electronic department and being requested to design and produce Printed Circuit Board (PCB) for the team. If you’re wondering what PCB is, just go open your CPU and take a look at the mother board. =)

Well, of course the PCB that I’m doing is not that high level yet la… After all, this is my first time designing.

PROTEL is one of the more popular software available in the market for this task. Though I’ve learned to use it a few years back, I’ve totally forgotten how to get it started =P. Spent a few days learning again.

The “raw” layout… web scattering everywhere…

Connecting every single pin MANUALLY…

Finally, complete layout with polygon

PROTEL makes the process of designing the board easier. However the process of connecting all the components together can really kill me. There’s an “auto-routing” function that can perform the task automatically but my board turned into nightmare after using it…sweat…

In the end, no choice… did it manually instead.

This simple little board is already killing me. I wonder how on Earth did those engineers designed the more advanced Intel processor boards…