The thing I teardown is a monitor detector. Because I bought it on second hand, first I need to figure out how does it work.
It has RF wireless signal detection, magnetic field detection and hidden camera detection. When the signal goes high, the screen will light up and it will vibrate. Also there are buttons and knob for you to adjust the function.
The teardown part is shorter than I thought, and here are the parts and the time-lapse video.
- knob for on and off and control
- nut that fixed the knob on the outside
- filter lens in the middle
- double-sided tape to fixed the battery
- GS probe for information transition
- lithium battery
- the part connect to the MC1
- font shell
- back shell
- two circuit boards, the upper one is DSK18D27, the lower one is DSK19A01 (I googled both of the name of the data sheet, but couldn’t find the exact one, and the searching result is very limited, maybe someone can teach me a different way to find the datasheet so that I can find out what the No.7 function)
For the circuit board, these two are soldering together.
In the front there are diode, two buttons, screen, piezoelectric Ceramic Buzzer(YXDZ) and some sensors. All the information transfer in and out from the middle of where the black, yellow and red wire lie. On the top you can see the the knob and on the right you can see the charger. On the back side of the circuit board, there are the leds and also the battery used to be attached to the back by the tape.
The tool I use:
Big and small screwdriver for open the shell, scissors for cutting the wire.
The difficulty about the teardown:
The shell didn’t have any screw to open, the only way to open it is to use the principle of leverage to open and it’s a destruction for the shell. In the video you can see me spending half of the time trying to open it. Firstly I found the holes in the device so that I can put the small screw driver in, and I tried to open from the wrong part, then I change the force from upper to the charger side where I put the screw driver into the device and finally open it.
The other thing I found a little went beyond my imagination is that all the functions are on the same (two) circuit board which are jointed and cannot be easily separated. Think about it carefully, integrated circuits are very common a long time ago which is great but for this specific assignment it narrow down the number of things I can teardown.
Three elements that interests me
- The integrated circuit board. When I knew this detector have all these function, it came to me that the inside must be very complex and maybe a lot of wires. But looking inside, they only use 7 wires for connection and all the parts are tiny even it buttons. The size of the parts make this kind of device possible to have a lot of functions at the same time.
- The way they put the battery is very interesting. They just tape it on the circuit board which is a quick and neat way.
- Also outside the “ugly” and functional knob is the beautiful and productized knob, which reminds me what is the role engineers and designers play in building a product.