We all have old obsolete devices lying around. If you have the time, then opening them up and salvaging parts is an effective way to learn a lot of things and yes collect some rare parts too.
It was time to bid goodbye to an old DVD player. I made this instructable as and when I took things apart and have tried my best to cover all the things possible.
Step 1: Getting Ready
Keep all your necessary tear-down tools ready. [ screwdrivers, pliers, tweezers, hammers (only if you are impatient :P).....]
Then look for the model number of the CD/DVD player that you are going to tear down. This is usually found either on the rear or one of the sides. In my case, it is a Phillips DVD player.
Using the model number look for its service manual or repair guides. (This step is recommended but not mandatory). You can use the following websites to find the one you need :
Then switch off the device and unplug all wires and cords from it.
Step 2: Getting Inside
Unscrew the enclosure. If you get stuck refer to the service manual (it may contain information about disassembling the device ).
⚠️ Beware of the big high voltage capacitors inside ⚠️
After I unscrewed everything I found a power supply board, a main board that does all the video and audio processing or encoding, a display board that shows the playback time, a mic input board for karaoke and finally the disc tray.
Checkout the image to see the different parts.
Step 3: The Parts: 1) Power Supply
The power supply is perhaps the best thing to salvage from such a device and is totally worth the time.
From the service manual, I got to know the voltages at the different connector pins.
I was pleased to find 5V, 12V and -12V all regulated DC outputs from a single board.
Uses: I could use this to run opamps that need voltages at both polarities and well I needn't explain the potential use of a 5V supply :P. And all this was present as a single isolated board. From the diagram below it is quite obvious that this is a well designed and stable supply.
Check out this instructable : https://www.instructables.com/id/Easy-variable-voltage-power-supply/
Step 4: 2. Segmented LED Display
Uses: Seven segmented displays are quite useful for different hobby projects including make timers, stopwatches,counters etc. I wanted to make a clock out of it but realized that it only has a single digit for the hour. This was because most CDs/DVDs had space to store only a couple of hours of video, hence it needed only one digit to display the hour. One could still do it just by utilising the 4 digits to the right and avoid showing the seconds.
The display uses an ET6202 LED driver which after a bit of googling appears to have been used with an Arduino too (check this ). So this looks like a good catch!
Step 5: 3. IR Detector
Looks like those standard 3 pin IR detectors out there.
Uses: They can be used with ICs like HT12E and HT12D which are encoders and decoders respectively to control many devices remotely. Here's an example project:
Step 6: 4. Buttons and Switches
One can find lots of pushbuttons and switches of different types.
The above was one kind of a cool switch I found inside. Check out the video.
Step 7: 5. Mic Jack + Amplifier
This board had a mic, an 8.3K potentiometer ( measured it using a
multimeter), and an amplifier. The pot is used to adjust the gain of the mic. This will probably only be present if the player has a karaoke feature.
Since there is an amplifier whose gain can be adjusted it opens up a lot of different potential uses.
Step 8: Opening Up the DVD Tray: 6. Motors
Took out the tray as a whole and slowly started removing things one by one. It had 3 motors in total :
- The one that slides the tray out so that a disc can be inserted
- To spin the disc
- To move the optical device along the radius of the disc so that all sectors can be read
All 3 were ordinary DC motors (in my case) but it's highly likely to get a BLDC motor from the spinning disc motor.
Uses: I needn't mention any as it's quite obvious.
Step 9: 7. Lens, Neodymium Magnets and More…
Took a closer look and found that the optical reader was from SONY.
Check out the above images for information on how to disassemble it.
The lens is suspended by 4 ultrathin wires and is held in between two neodymium magnets. The four wires supply current to the coils that run around it. Check out the video to see how it's held in place.
Putting it to use:
I took the lens out carefully and held it in place just in front of my phone camera to try and see if it augments the camera. Took some macro shots (couldn't find anything so I used my finger) and the results are pretty interesting as I think using the lens brought the focus even closer.
Then curiosity got the best of me and I tried putting the lens above my phone screen to try and see the pixels. The pixels which were otherwise very hard to see were visible. The combination of different hues that make up totally different colours on the screen was quite a sight. (Check out the images for more)
The optical source:
This is what apparently produces the light to read the disc. It after a series of reflections using special mirrors and combination of lens reads data from the disc.
Step 10: What Remains:
This board is mostly made of SMD components that are not so easy for hobbyists to handle. Though the board has components like
- VIDEO DRIVER
- MOTOR DRIVER
The time and money you put into making some use of it will far cross the actual value of the component (or it won't be so easily usable). Hence I usually discard them.
Tip: Do check out for things like heat sinks and rare-valued capacitors or very large resistors. They can be quite useful.