Dissecting a CD Player

For the last year, one of our CD players has been acting up – skipping in the middle of a song, taking a really long time to start playing the first song, that sort of thing.  In the last month or so, it stopped playing CDs at all – it would just spin and spin, and eventually give up.  We decided to retire it.  CJ asked if I wanted to take it apart with the girls as a project.

Like you had to ask!

Lucy was thrilled at the idea of taking it apart, so we decided that would be our next project.  We wanted to do it on a weekend, when we wouldn’t be as rushed as on a weeknight, but weekends are a precious commodity around here.  Lucy’s people and my people had a heck of a time finding one that worked for both of us.  Ahem.  As it turned out, this past weekend worked for both of us.

I told Lucy to head down to the workshop, and I’d be there in a minute.  I joined her a minute later, only to find this waiting for me on the workbench:


What the?!  You’re looking at the head from our first robot project, sitting on top of the CD player, with my safety glasses on.  Lucy just giggled.

Anyway, the CD player.


My first question to Lucy was, where do we start?  Lucy responded, "I have no idea."  Well, take a look at it, turn it around, see how we can get into it.  She did, and after a minute responded, "I think we need a screwdriver."  Ok, which one?  I have several.  "One that looks like a diamond."  Ah, that’s called a "Phillips" screwdriver.  I always thought it looked like a "plus" sign.  "Oh yeah.  We need a Phillips screwdriver."

And we were off.


8 screws later, we had the bottom case off. 


Our next task was to cut the wires leading to the battery compartment and the transformer for the AC jack.  I took a moment to describe what the latter did.

Next we needed to cut a couple of other wires that were in our way of the main circuit board.


Now we could focus on getting that board up and out, and see what the innards of this CD player looked like.


Another 5 screws later, and we got it.


We spent a while going around the board, pointing out the white knobs used to adjust the volume and radio tuning, the resistors, the capacitors, the digital display (shown in the far bottom), and some of the other components.  I also pointed out that the lines on the bottom of the board were really wires that connected everything together.

Next, we extracted the laser that actually reads the discs (well, ok, "read" – past tense – the discs):


I showed Lucy that there were two motors – one that spun the discs, and one that moved the laser reader back and forth to read them.

While she was playing with the laser reader, I extracted the circuit board that held the buttons for play, fast forward, etc.


I explained that these were "momentary" switches, because they would only turn on while you pushing down on them – only on for a "moment".

And then we extracted the speakers, and we had lots of fun playing with the embedded magnets.


Lucy thought they looked like flying saucers, but they needed guns to do battle.  Muhahahahaha!

So she "armed" them with some of my small screwdrivers:


Several days later, I realized that had a really fun, and unplanned, consequence.  The screwdrivers had become partially magnetized, so we had some fun seeing that in action.

Overall, this teardown was most excellent, and time well-spent.