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[13 July 2022] Back in the day when these things were the music player of choice I had a portable CD player (Goodmans-branded, right). It served me well for a good few years until, if I remember correctly, it stopped being able to read discs (I still have the carry case I used with it though!). I also had a Hi-Fi (also Goodmans-branded) at the time of which the CD player also stopped reading discs - I continued using the system by rerouting the audio from the player to some make-shift Aux-In sockets (something the system lacked), providing further years of use until the amplifier seemingly got tired and it grew quieter and quieter!

This inability to read discs, I believe, is a common issue typically caused by the laser wearing out (assuming dirt has been ruled out) - surely this can come about more swiftly if using scratched discs as the laser has to do more work to track and focus. Whatever the reason, I no longer have that player (or Hi-Fi), but I recently acquired another, in the form of this cheap find from a thrift store:

Sadly this turned out to be faulty too. However, it did briefly read a disc, in fact I played a whole album without fault - the problem was with getting the player to switch on at all, indicating to me that it wasn't a laser issue.

I have now dismantled the player and tried various things to test and get it into working order, but with little overall success.

Could it be:

  • A battery leakage? (there were some signs of a minor leak at some point)

  • A faulty ribbon cable that leads from the main circuit board to the controls and display module?

  • A faulty control board?

  • A lose component or faulty capacitors?

  • A combination of the above?

It seemed to me that it was a faulty ribbon cable which is somewhat unique to this player since it has the controls and display on the lid, and thus the ribbon is repeatedly flexed. The buttons also seemed like they could be fragile due to this being a particularly cheap (later) player (rather than being an early one of a reputable brand).

I managed to dismantle the player, first by removing the screws from the base, then prying the base off, being careful not to break clips or damage the sockets and controls that run down the right side of the player.

I first inspected the board and the possible corrosion issue, and checking if any components were lose. I also manipulated the ribbon cable to see what effect that would have but the fault was so persistent and random that it was hard to tell.

All pretty "simple" and cheap inside.

One odd and concerning thing I did discover was that I also found in the thrift store the Crown-branded AC adapter that was supposedly donated with this player; the ratings matched, but upon testing it with it plugged in (because the power jack was too small to do so independently with my multimeter) that instead of putting out the rated and required 4.5V, it was producing 7V. I was concerned that this over voltage (the player can also run off 2 x AA batteries which would be no more than 3V) would have caused damage. However, I have also guessed that this apparent over-voltage is produced while there is no load while the player is not operating - I have not yet been able to confirm this though.

Moving on and it seemed the ribbon cable where it slots into the board could be an/the issue.

I tried detaching the ribbon cable and using deoxit there with no improvement. I also slipped a slither of thin plastic down into the slot to ensure better contact... with the contacts, with little to no improvement.

At a loss I proceeded to dismantle the lid of the player where the ribbon cable runs to (out of sight) and controls are housed. This was more involving.

I couldn't see how to actually remove the lid hinges from the top section of the player (there are essentially three layers of plastic: the base, the layer beneath the CD, and the lid), and this needed to be done in order to gain access to one last remaining screw. However I devised a plan.

Rather than risk breaking something or proceeding with the ordeal of prying the hinges out of place, I drilled a hole through the plastic to reveal that last remaining screw in the layer beneath; this area being out of sight at the rear of the player and beneath the lid when closed. I removed the screw and finally I gained full access to control board so I could inspect and test the ribbon cable attachment and buttons.

Testing here was sadly still inconclusive but I elected to carefully "reflow" the solder for the ribbon cable. I have seen someone else fail to do this (on Youtube) on a device by using a soldering iron that was too hot and melted the ribbon cable, so I used my lowest wattage iron, a USB powered one that is pretty useless for most things, added some liquid flux and carefully and briefly touched the iron to each solder point. It made a reassuring sizzle and each contact seemed to sink into place in turn. I was hopeful and initial results seemed promising, but as I proceeded further and further towards full reassembly, it became apparent that things still weren't working right.

I should add that I can hear (and see) the laser module move slightly when the Play/Pause button is pressed to power on the player, providing it is going to switch on. The display would then always operate. But sometimes a few presses would be required and I kind of came to assume that three presses were necessary to get this far, but perhaps this is indicative of the underlying fault.

The buttons are actually covered with a layer of tape,
seemingly to prevent dirt getting into them and preventing contact.

The player is still intermittent in its ability to switch on, and I also noticed that not all of the buttons work anyway; if I can get it to switch on play and then I can usually skip tracks ok, but Stop never works. I was able to get some of the other buttons to work, but then they stopped responding - to me this seems not to be ribbon-related since I would be careful not to move this between tests so that I wasn't incorporating multiple variables into my tests. I had also continuity tested from the button pads to the far end of the ribbon cable indicating to me that the buttons themselves were operating ok.

One other peculiarity was the way the ribbon cable was routed through the plastic; there seemed to be a specific slot for this (2), but it had been sent through a wider opening (1) - was this intentional during assembly or a mistake? It did actually seem better through the larger opening.

My conundrum so far:

  • Is the ribbon cable still not perfectly attached?

  • Is there an additional/other problem - namely (a) problem capacitor(s)?

I think I will either reattempt the solder flow on the ribbon cable - if brave enough I could detach it entirely and attempt to reattach it - and/or failing that I could replace some capacitors, beginning with the one closes to the power source.

If all else fails I have seen that similar players are available on ebay with assumed faulty lasers and the laser from mine (assumed good) could be quite easily swapped to one of those to produce one good player.

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