How Stuff Work

Fixing the Car Window - 15 Oct 2006

The Problem

Bill bought a used car on Sep 15th, 2006 (a 1998 honda civic dx, 88k miles, $3.5k), and the car window was having problem rolling down.

The Solution

Instead of paying someone to fix the car, Bill (stupidly) decided to fix the car window himself. With the help of Bill's landlord, the car window was able to roll down.

Breaking Bill's FOSA Laptop  060828

After 5 years using the FOSA laptop, the laptop finally stops working. FOSA is an american company, but Bill bought the laptop in Hong Kong.

My roommate Yaniv Rosen, a physicist, was looking at the broken laptop. The sign said "Laptop RAPED by Bill Hung"

Breaking a Printer - 4 Feb 2006

This Epson InkJet Printer of my roommate is broken, so I take it apart to get the power supply and the motor. This printer model was quite popular because of the low price.

The internal of a printer looks like this, the rail is for the ink box to slide around. You see the control wire at the front (the white flat one).

If found the control board of the printer. The board is small, but handles USB and parallel interfacing. 2 Epson chips at the front and 1 Epson chip at the back. The LED is what appears as the status light on the printer. The wire at the bottom is the power supply.

The motor unit on the left, this motor is tiny. Controlled by 4 wires, looks like a typical stepping motor. The flat wire controlling the ink box is shown on the right.

Breaking a Keyboard  - 4 Feb 2006

I spilled some water on the keyboard, and it stopped working. It is hard to get a Japanese keyboard in the US. I had to take everything apart for wiping. And fortunately the keyboard works at the end.

The keyboard has the button front, a white plastic button sheet, then a plastic wire sheet (2 layers capacitors), then the back cover with a chip unit on top.

Here I was testing the alignments of the keys to see if the keys need more wiping. Pressing the keys like this has to be done with the computer on so I can see the letters on the screen. The chip unit was not stable, so I put some tape on it to fix the position between the plastic sheet and the chip unit.

Here clearly shows the 2 layers of wiring, if the wires from each layer touch each other, a short circuit will give a signal to the chip unit on top. The keyboard side of the chip unit has 26 pins corresponds to the coordinates of the keys. The chip unit will then generate a signal to transmit to the computer through 4 wires.

Here shows the layout and the packaging of the keyboard chip.

The front button is a mechanical device.

Close up on the 2 sheets inside a keyboard.

Breaking a Webcam   - Spring 2005

I have read an article about turning a normal webcam into a infra-red camera. So I took out my old webcam-DC dual use camera, trying to turn it into an infra-red camera.

Breaking a webcam, intended to make an Infra Red camera, because this is a Charge Coupled type camera. Later in the project, the camera just died.

Breaking an AC-to-DC Transformer  - Spring 2005

I opened up a AC-to-DC Transformer, and I drew the circuit for the transformer. This transformer consists of 3 capacitors and 2 resistors. The circuit design is a very common one. Simpler than the AC-to-DC Circuit I made.

Breaking an Plug-in   - Spring 2005

A Hong Kong three-legged type of plug-in. Squared-legged with a fuse built-in.

Breaking an IDE cable   - Spring 2005

I wanted to know how the IDE cable is actually connected. They have a metal trap that hold the wires. I need to break the cable for my microcontroller programmer.

Breaking a Joypad Handheld Controller   - Spring 2005

My CS 150 Digital Design project uses a controller, so I wanted to know what is in the controller. The controller is made with surprisingly simple circuits. Some rubber pads with a small circuit attached.

Breaking a Laptop   - Spring 2005

My friend's laptop was having problems, so we took the laptop apart.

Tools

Resistors Paper Box