Thursday, February 25, 2010

Disassembling an old phone

Disassembling an old phone
The major benefit of disassembling old electronics is getting electronic components such as transistors, capacitors, resistors, On/Off switches and even leds.
Let's start
I have two old phones this is one of them:

In the beginning the whole disassembly process was in order to get the phone LCD shown in the above picture, but actually discovered that its wire are damaged near to the input, so nothing to do only continue to get other components;

Plenty of them.
Turning on my iron to start getting resistors at first because they are the easiest components in disassembly process.
After more than 2.5 hours (because I am a beginner to electronic it takes that time from me) of working I finally got these:

And still many components on the board:

If you are thinking about doing the same thing; there are some notes you have to consider:
1-     Almost all electronic components are sensitive to high temperature, so try to do use the iron efficiently, if you expose those components legs to high temperature they will be damaged, actually some electronic components have a printed temperature degree on their back, for example -15 +55 (that means not less than -15 degree nor more +55).
2-     The disassembled devices might have some components not working so after getting them use your multimeter to check if they are working properly.

That’s all for today.
Good luck.

Tuesday, February 23, 2010

Understanding Keyboard wiring and Keyboard works

Understanding Keyboard wiring and Keyboard works

As this is the First day, I went to my keyboard (Damaged Keyboard) to try to understand the wiring inside it and how to get benefit from it If I decide to use it in bigger projects:
The notes that I liked:
1- The input volt in the keyboard is +5V
2- After I checked the nature of wires, I realized that there is no standard tasks for wire, for example the red wire should be for the +5V but (using my multimeter) I noticed it is not, the +5V wire was the White wire, the common wire was the Yellow wire.
3- Now we have four wires (Red, White, Yellow, Green), this remind us about the four wires in USB cables, once I solder the wires to their right places in the chip, see the signs in the chip as the following picture:

4- I turn on my pc to get the message "Keyboard error or no keyboard present" and " to continue", I tried to press F1 but my keyboard was not working.

5- By using multimeter (Checking continuity) I could track wires from the PS2 output to the wires,
and by using the information in this site:, I knew that there are two wires not working properly the data wire (Red one in my keyboard) and the +5V wire, the clock wire (Green) and common wire were good.

6- The lesson that we can understand from this is that we can use the small chip of the keyboard

to receive multiple combination from keyboard or from any other sources if we care about the input and output voltage, the data output from the chip is 11 bits output we can transfer it to any meaningful output, inside the keyboard there are two layers of thin and transparent plastic with conductive lines;

We can use it in any application, may be in the near future at this blog.


Monday, February 22, 2010

Hello World

Hello World
It is just a test