Vintage CD player repair : Philips CD 371 AKA Radiola CD 1371

[shakalnokturn]

I think your plan to throw the odd lens on the pickup and see how it goes is reasonably insane.

I like your style 

I guess it only foes to show that yet again.... newer does not always mean better....

Thanks, I'm sure this one was a purely unintentional mistype. Like your style too anyway 

The track selection rotary encode on the front panel that's playing up.... can't possibly sell it like this. Need to have a closer look at it. Hopefully it's not sealed and I can spray some contact cleaner in it...

The best I've found for those situations without disassembling or replacing is to stand the axis upwards, trickle a small amount of white spirit down it, rotate plenty until you feel a difference, trickle some contact cleaner the same way, rotate plenty.
The grease stiffens enough to cause problems.

It makes a horrible noise when it closed (it's fine/quiet when opening).  Looks like the gear that catches and drives the tray, has problems catching the track underneath the tray.

IIRC that's typical of a bad mechanical sync the driving gear is probably a tooth or two ahead (or late). I've also seem some trays that would vibrate on their worn plastic sliding guides, some grease usually does the trick here.

[Vince]

I guess it only foes to show that yet again.... newer does not always mean better....

Thanks, I'm sure this one was a purely unintentional mistype.

Typo it is, of course ! 
Had to be a typo because I didn't even know that word existed at all !     
Had to look it up... now thanks to you pointing out my typo, I added a new word to my vocabulary... though not sure I would get to use it, seeing I never heard or read that word since 1998 when I moved to the UK.  But Mnem over on TEA likes to use weird words and expressions so maybe he will use it one day and I can say AH, I KNOW THAT ONE ! 

The track selection rotary encode on the front panel that's playing up.... can't possibly sell it like this. Need to have a closer look at it. Hopefully it's not sealed and I can spray some contact cleaner in it...

The best I've found for those situations without disassembling or replacing is to stand the axis upwards, trickle a small amount of white spirit down it, rotate plenty until you feel a difference, trickle some contact cleaner the same way, rotate plenty.
The grease stiffens enough to cause problems.

Took the front panel board out to have a look at the encoder. It was pouring out what looked like perfectly fresh/good grease out the shaft. So I was rather dubious that its misbehaviour would be caused by crusty grease or dirty or corroded contacts inside. So, since I am lucky and it turns out it's NOT a sealed encoder, I immediately proceeded to open it to see what I could find inside. Glad I did. It was immediately apparent that the grease and contacts were just fine, and that the problem was most likely rather mechanical in nature : see macro shot of the thing below. There are 4 contacts/wipers in the thing, one in each corner. The two bottom ones (circled in green), which each have 3 "fingers", look fine. They are electrically connected together and form the "common" pin of the encoder. However the wipers in the top left and top right corner, which correspond to the two "channels" of the encoder (circled in red) look out of whack eh ?  They each have two fingers. The left wiper has its fingers collapsed, touching each other. The right wiper had its fingers spread apart , forming a Vee shape.  So I bent all these fingers back into shape, then bent all fingers of all 4 wipers a little upward, to make sure I get a good contact/spring action on the shaft. Then put it all back together and I am glad to report that it now works SO MUCH better and more reliably ! I consider this a fix. Works plenty well enough for me to sell it without shame.

That's the first time I ever take an encoder apart, never mind try to fix it, never mind successfully ! So it's quite encouraging ! I therefore won't hesitate to do it again if need be. It's quick and easy to do. Just need good eyes and a very tiny flat head screw driver.

It makes a horrible noise when it closed (it's fine/quiet when opening).  Looks like the gear that catches and drives the tray, has problems catching the track underneath the tray.

IIRC that's typical of a bad mechanical sync the driving gear is probably a tooth or two ahead (or late). I've also seem some trays that would vibrate on their worn plastic sliding guides, some grease usually does the trick here.

Found the problem for that one too ! Not a sync problem. I was simply missing a little plastic piece !
See picture... there is a little black plastic bearing/bushing/roller whatever ever you want to call it, that mounts atop the axis of the gear that drives the tray.  With this piece in place, the gear is now perfectly sitting inside the track under the tray, no play, no bending possible... works like a charm, problem solved !!   

I fond this plastic piece laying on the bench, not knowing WHERE it came from ! Was wondering where the hell it was supposed to go... was totally clueless. Then I thought hey, looks like maybe it could fit on top of the gear ? It fit perfectly ! So I checked the manual for the relevant exploded view of the mechanical stuff, and yes indeed, it show this piece in there, no doubt !
So, since it was looking good, I put the tray i place, powered the thing on, and it worked perfectly first time ! It was that simple  ! 
I was not doing anything wrong, I was just missing a stupid little part without knowing ! 
I guess it must have stuck (due to the grease) to the underside of the tray, when I initially removed it. That way I did not notice it. Then after handling the tray 2 dozen times on the bench while working on the player, the little bastard must have come off and fell onto the bench... for me to notice much later then wonder where the hell it came from ! 

Anyway. all problems solved, this player is fixed ! I put it all back together, just need a little clean before I take pictures of it, then off for sale ! 
Pickup is tired I think, since it can't read my CDR, and is on the slow side at detecting regular pressed CD's... but well, laser can nont be adjusted on this particular unit, so I will have to leave it like that. it works none the less, so sorry, will sell it like this... 

So in the end, all it needed was a couple belts, and the encoder taken apart ! too bad I spent 10+ euros to buy the belts on ebay rahter than getting them from you... I just wasted a good part of my profit margin, too bad. Luckily the drive was given to me, so cost me zero. So any money I make above 10 Euros, is profit.
I am thinking sometimes of registering a side business, a "fake" one, just an empty shell, just so I can have a registration number so I can be eligible for a "pro" account with spare parts suppliers like you do. From what I gather, it takes only a few clicks on the interweb to register a small business, it's free and you don't pay any taxes if you don't make any significant money. So it should not cost me anything to have a "business"... would need more digging to confirm this, though, or course ! 

So I have managed to fix 3 more Cd players then... that Sony changer, third one, then the Philips CD824, then the super mega crappy Philips CD720.
Let's try to flog all that now !   

See, Gyro ? I am getting rid of them, bit by bit ! 

[Vince]

Shakal you won't believe it ! I did it AGAIN : I have just sold that Sony changer ! 

First too at an incredible 40 Euros in just a few days and without even any attempt at negotiating the price... doing it once was incredible enough, but doing it twice is... a statistical oddity ?!  too good to be true.

well, now it's not two but 3 in a row !

Given that at 40 Euros the first two sold so well, I increased the price this time to a silly high 65 Euros, just to see what would happen ! 
Got lots of "views", 50 or so, amazing in itself, but no takers, nobody contacted me. After only 7 days I lowered the price a bit to 60 Euros, still through the roof.

https://www.leboncoin.fr/image_son/1988296127.htm

Guess what ? Last night, only 4 days after updating the price, AGAIN a guy took it, full price, no questions asked no nothing ! He didn't even message me, he simply clicked the "buy" button on my ad page, that's it !!!      How can that be !   

3 identical stories in a row, it's beyond the laws of physics ! I think I just found me a new job ! 
Good thing because I am about to lose my current one... they are dicks and I need to quit real fast before my mental health goes haywire. 

Now need to go out today to buy some packing material so I can package it properly, as promised in my ad...

[shakalnokturn]

You must be kidding, either that's a lot of good luck or something in your adverts reassures buyers.

I suppose mentioning that players have been serviced and that you'll accept returns does help in some way but maybe the most reassuring is seeing all the test equipment in the background... It gives you the impression that they're coming from a repair shop. Your pictures actually made me want a CD player oscilloscope 

I have a nice JVC XLV-264 to sell I'll try a higher price on that one, unfortunately I have less of an electronics lab than you do, I won't be able to have a nice TE background in my photos...

I remember your topic on the Radiola CD player with a defective LED driver, funnily I'm trying hard to save a DSO (that doesn't want to be saved), last night troubleshooting problems in the front-end PCB I ran in to two M5451 shift registers. Obviously here they're not used to drive a display.
https://www.eevblog.com/forum/testgear/gould-ultima-nicolet-accura-dso-software-needed/msg3582435/#msg3582435
(One of the longest and least captivating TE repairs of all times, all the same I did get a little more input than for the OX 2000 DSO...)

[Gyro]

I remember your topic on the Radiola CD player with a defective LED driver...

It may seem strange now, but that was this thread. 

[shakalnokturn]

I remember your topic on the Radiola CD player with a defective LED driver...

It may seem strange now, but that was this thread. 

Yes, I realised that just after posting 
Didn't care to correct myself, feeling that getting confused on the topic was saying something anyway.
I vote the topic should be renamed: "Vince's CD players...(To be continued)"

[Vince]

You must be kidding, either that's a lot of good luck or something in your adverts reassures buyers.

I suppose mentioning that players have been serviced and that you'll accept returns does help in some way but maybe the most reassuring is seeing all the test equipment in the background... It gives you the impression that they're coming from a repair shop.

Yes I try to put in my ads everything that I would want to see if I were a buyer. There is a gazillion old CD players  for sale but none that inspire any level of confidence. So I try to instill as much confidence as I can... I think that's what makes them stand out and it appears to work. So, I keep in that vein...

Your pictures actually made me want a CD player oscilloscope 

Hey look what appeared just now :

https://www.leboncoin.fr/equipements_industriels/1995475661.htm?ac=206978287

Been a while since an affordable 700 series has been for sale !
As for me I am waiting for a TDS 784D (or better yet a more rare 794D...) one day, when I am rich and no other priorities.

I have a nice JVC XLV-264 to sell I'll try a higher price on that one,

Hmm... a few for sale on Ebay. Usually prices on Ebay are inflated, yet this particular model seems to sell for very little 
One for 39 Euros on offer, another for 25 Euros "buy it now"...

unfortunately I have less of an electronics lab than you do, I won't be able to have a nice TE background in my photos...

I can't quite believe that !   

You are the pro, I am just the hobbyist here !
Only decent piece on my shelves is the TDS544A but YOU sold me that one !   
Oh yes, I have a cool TDS 694C, 3GHz 10GSps on each of the 5 channels... but of course like of the 694C, the trigger IC's are cooked so it can only trigger manually or from the external input. But still cool !! I can always get en external trigger circuit and hook it to the external trigger input...
There is still lots of basic TE I don't have ! For one you have a cool EPROM reader, indispensable tool !
And you have a life time experience fixing stuff, I can't buy that ! 

I remember your topic on the Radiola CD player

I sense a bit of sarcasm here ?! 

Yes, YES, I will get round to wiring that chip and get the player to display something other that garbage, I promise !!! I apologize deeply for the delay, I know I suck ! 

with a defective LED driver, funnily I'm trying hard to save a DSO (that doesn't want to be saved), last night troubleshooting problems in the front-end PCB I ran in to two M5451 shift registers. Obviously here they're not used to drive a display.

Hmm, interesting indeed...

https://www.eevblog.com/forum/testgear/gould-ultima-nicolet-accura-dso-software-needed/msg3582435/#msg3582435

Wow.....just.... wow.... I admire your perseverance on that one !!!! 
I had my share of GOULD scope last summer, never again. Just crap, utter crap, no more... no more ! 
That one is decent spec but not worth your time... so much time spent and hair pulled because of it already ! You will never get your money back, give up before it drives you completely insane !     Even if you manage to fix it, nobody will want it, or not for a a lot of money anyway... A TDS 500 Tek with similar spec no problem,  but a GOULD....  it's like you old Lecroy scopes, IIRC they did not sell easily (have you actually managed to sell them BTW ?! )

I am thinking that making a profit is not your primary goal... I think it's more a mix of masochism and the love for a good technical challenge, and hating giving up. You just can't take NO for an answer !!! 
I mean, how many people do you know that would fix a TDS 500 CRT with a Minitel fly back transformer ? You're the only one my friend !! 
I do admire you for that... my Minitel hero.

(One of the longest and least captivating TE repairs of all times, all the same I did get a little more input than for the OX 2000 DSO...)

I have given up on Metrix scope. They just are junk and made NOT to be fixed/serviced. I hate them, I don't touch them, not even with a barge pole, even a super long telescopic one...no. Just... no. Not to mention the consistent lack of service manuals. Metrix just didn't give a shit about serviceability.
I would even say it's worse that than that GOULD 1604 I fixed last summer, and that does say something !!!

[Vince]

Yes, I realised that just after posting 

Oh, so there was no sarcasm above then, sorry ! 

I vote the topic should be renamed: "Vince's CD players...(To be continued)"

No no no, I WILL get round to fixing the Radiola, I promise ! I have bought and received all the parts, gotta do something with them now !   

[shakalnokturn]

Let me help you take this even further off-topic 

Yeah I saw that TDS 754D. If he'd let it go for 200€ maybe...
I have enough scopes for now and just spent some money on a (hopefully working) spectrum analyser.


I'm not much of a pro lately, haven't been finding much time for electronics. I do have a decent weight of TE, just nowhere to expose and use it conveniently for now.

A pitty for your TDS 694C, are you aware of this:
https://www.eevblog.com/forum/testgear/least-expensive-but-reliable-used-market-scope-with-at-least-1-ghz/msg791170/#msg791170
I think I've seen more detailed information around on that solution, maybe not specifically on the 694C though. If curious ask around...

I'd be curious to see if an alternative fix to the trigger could be done with something like an ADCMP580 (/581/582) if someone with a working scope can document the ins and outs of the original IC.
You probably don't even need that fast a comparator as long as jitter is low enough.


You're right, Gould and Metrix belong in the same nut sack, the best Gould I've had so far was a Hitachi rebrand.
The idea of the Gould Ultima 500 isn't that bad, just the way they've stitched the wretched thing together is pretty degrading, besides the one I was sold was a compilation of defective parts.
SWMBO said the same as you: "you're wasting your time, it's an unknown model no one will buy it"
Anyway you're right I won't take a NO from a machine. Either it ends repaired or axed. I'm getting there slowly... (Looking for the axe right now  )

Yes I sold the LeCroy's 9344C, 9354, 9450, Metrix OX2000 (easier than expected).
Also the Tek 2230, TDS 320, Hameg HM203-7.

[Vince]

Let me help you take this even further off-topic 

Yeah bring it on, I like it when you talk dirty OT to me ! 

I have enough scopes for now and just spent some money on a (hopefully working) spectrum analyser.

Hmm yeah, dreaming of one all the time, but sadly cheap defective old HP units still cost fortunes even broken, so once you dial in the gamble they represent, it's not worth it, might as well buy a brand new one for not much more, that works ou of the box, more reliable, and comes with a guarantee.

I'm not much of a pro lately, haven't been finding much time for electronics. I do have a decent weight of TE, just nowhere to expose and use it conveniently for now.

Shame... last summer when I was sweating rfioxing this horrible Gould scope, you said you were performing your talent on the dining table because the new house was still not finished ?!
That's extreme... lab room still not habitable ? Still no bench, still sharing space with the chicken and salad ?

A pitty for your TDS 694C, are you aware of this:

Ah yes I had forgotten about that ! Yes I must try it one day ! But I need to use a decent hot air station if I want to stand a chance of success. MY cheap 40 Euros station just won't cut it, I would just ruin the board...
Need a "Quick" station or its recent clone from Atten, which I saw priced as low as 150 Euros  ?!  MIght have been a promotion don't know, but still.
Price has now become affordable so I will definitely get one in the not too distant future.

I'd be curious to see if an alternative fix to the trigger could be done with something like an ADCMP580 (/581/582) if someone with a working scope can document the ins and outs of the original IC.

Wow, how do you know the pinout and functionality of that chip is the same as the proprietary Tek chip ?! Quite a gamble eh ?! 
Or you mean use that chip as an external circuitry feeding the external trigger in put of the scope, as I suggested yesterday ?

besides the one I was sold was a compilation of defective parts.
SWMBO said the same as you: "you're wasting your time, it's an unknown model no one will buy it"

A wise wife it must be, she is a keeper  ! 

Anyway you're right I won't take a NO from a machine. Either it ends repaired or axed. I'm getting there slowly... (Looking for the axe right now  )

I will send you an axe to shorten the agony, just tell me your favorite colour ! 

Yes I sold the LeCroy's 9344C, 9354, 9450, Metrix OX2000 (easier than expected). Also the Tek 2230, TDS 320, Hameg HM203-7.

Oh, quite successful then ! All the Lecroy sold in the end, good ! 
Didn't know you had a 2230. I contemplate one just to complete my Tek 2000 series "collection"... but have obviously zero need for it given I have a 2232 already... which is in need of a little TLC / fixing up when I get time for it... beam just won't focus, scope did not like its year spent in storage... neither did my rack mount type 5111A that's now extremely ill, poor little thing 

CDM12.1 ..... the 30 year old salvage one that the Ebay china seller pretended to be NEW. I let it pass originally, 2 weeks ago when I received it. Didn't want to bother. So I left no feedback good or bad,  just ignored the guy.
Unfortuantely (for him), yesterday he sent me an (automated I guess) e-mail ASKING me to leave feedback, and even going as far as INSTRUCTING me to leave a  5 STAR feedback !!  This guy is provoking me ?! Is he suicidal or what ?!
So this time I obliged and left a minus 20 star review, with a comment telling it how it is, basically " RUN AWAY  !! Kepp your money, prenteds its new but is clearly a 30 year old crusty salvaged unit, and the pick-up flatflex is not even shorted/clamped !!!  KEEP YOUR MONEY RUN AWAY  as fast as you can !!! ".

Guy replied saying hey you can't leave me  negative feedback, it will hurt my business badly !!! Let me give you a partial refund (paid 10 Euros for the thing), let's talk !!.

Did not reply. Today he wrote again, BEGGING me to find a solution, to discuss, call me his "friend" (eh ?!  ), and this time offering a FULL refund...

I am done with this guy, I won't reply to any of his messages. He fucked with me and asked me for my feedback, now he needs to be held accountable for his actions ! That's life sorry bob ! But I am not worried for the Ebay "reputation" of his business.... I am sure one of his Chinese buddies already has developed some virus/malware that can manipulate the Ebay servers to removed negative reviews from this account all by magic !!!

How can these scum bags of sellers fuck with people and seriously expect to be get a 5 star review with just a couple Euros refund ? Do they think they can buy people with some silver money ? Really ?     You can keep my 10 Euros my "friend", and also keep my negative review,  FUCK YOU !!!!!   

[shakalnokturn]

Shame... last summer when I was sweating rfioxing this horrible Gould scope, you said you were performing your talent on the dining table because the new house was still not finished ?!
That's extreme... lab room still not habitable ? Still no bench, still sharing space with the chicken and salad ?

Still the same uncomfortable situation, not moving fast.

Ah yes I had forgotten about that ! Yes I must try it one day ! But I need to use a decent hot air station if I want to stand a chance of success. MY cheap 40 Euros station just won't cut it, I would just ruin the board...
Need a "Quick" station or its recent clone from Atten, which I saw priced as low as 150 Euros  ?!  MIght have been a promotion don't know, but still.
Price has now become affordable so I will definitely get one in the not too distant future.

I get plenty done with my Atten 858D+ sometimes a little preheat from underneath makes all the difference. I find the tool would gain a lot by having a supple silicone cable. Make sure you train on disassembling various types of PCBs.

Wow, how do you know the pinout and functionality of that chip is the same as the proprietary Tek chip ?! Quite a gamble eh ?! 
Or you mean use that chip as an external circuitry feeding the external trigger in put of the scope, as I suggested yesterday ?

Neither really... I seriously doubt the ADPCM580 has a similar pinout, functionality I expect to be very close.
I wasn't thinking of use on Ext Trig. either, but rather fitting it in the scope in place of the defective Tek trigger IC's, either dead-bug style or on some kind of adapter board/flex.

Oh, quite successful then ! All the Lecroy sold in the end, good ! 
Didn't know you had a 2230. I contemplate one just to complete my Tek 2000 series "collection"... but have obviously zero need for it given I have a 2232 already... which is in need of a little TLC / fixing up when I get time for it... beam just won't focus, scope did not like its year spent in storage... neither did my rack mount type 5111A that's now extremely ill, poor little thing 

I sold all the LeCroy's I wanted to sell, still have a DDA-120, LT354, 9354M, 9354L, 9344, 7200, shattered 9384...
Funny your 2232 is out of focus, when I switched my 2230 on after almost 2 years storage because I decided to sell it, it was out of focus too, checked all the high value resistors, cleaned PCB and other obvious stuff but it turned out that replacing the Murata HV multiplier solved the problem. Although working, the replacement part was far from new, this further motivated me to sell the scope ASAP...

CDM12.1 ..... the 30 year old salvage one that the Ebay china seller pretended to be NEW. I let it pass originally, 2 weeks ago when I received it. Didn't want to bother. So I left no feedback good or bad,  just ignored the guy.
Unfortuantely (for him), yesterday he sent me an (automated I guess) e-mail ASKING me to leave feedback, and even going as far as INSTRUCTING me to leave a  5 STAR feedback !!  This guy is provoking me ?! Is he suicidal or what ?!
So this time I obliged and left a minus 20 star review, with a comment telling it how it is, basically " RUN AWAY  !! Kepp your money, prenteds its new but is clearly a 30 year old crusty salvaged unit, and the pick-up flatflex is not even shorted/clamped !!!  KEEP YOUR MONEY RUN AWAY  as fast as you can !!! ".

Guy replied saying hey you can't leave me  negative feedback, it will hurt my business badly !!! Let me give you a partial refund (paid 10 Euros for the thing), let's talk !!.

Did not reply. Today he wrote again, BEGGING me to find a solution, to discuss, call me his "friend" (eh ?!  ), and this time offering a FULL refund...

I am done with this guy, I won't reply to any of his messages. He fucked with me and asked me for my feedback, now he needs to be held accountable for his actions ! That's life sorry bob ! But I am not worried for the Ebay "reputation" of his business.... I am sure one of his Chinese buddies already has developed some virus/malware that can manipulate the Ebay servers to removed negative reviews from this account all by magic !!!

How can these scum bags of sellers fuck with people and seriously expect to be get a 5 star review with just a couple Euros refund ? Do they think they can buy people with some silver money ? Really ?     You can keep my 10 Euros my "friend", and also keep my negative review,  FUCK YOU !!!!!   

I'm not sure how eBay functions these days, all I know is that I much dislike it on the whole. I recently gave negative feedback for that non-new PCI9050 bought for the Gould DSO, next time I checked the negative feedback had been removed... I then tried the "want to return goods" procedure saying that either I wanted money back or to leave them the feedback they deserve. I'm meant to be refunded (maybe) even if I have no intention of returning the part.

Anyway, let's get back to CD player LED drivers.... 

[Vince]

OK... 3+ months later, I am back on CD players ! 


I have run out of luck selling them. The first 3, the 5 CD changer Sony players sold extremely well, in a matter of days and for top money, 50/60 Euros... then and bit later I managed to sell the crappiest of all my players, the Philips CD720 IIRC, for 35 Euros, a miracle.

But the Philips CD824 that I spent 10+ euros to replace the gear/belt kit for the tray... doesn't want to sell, even though I advertise it half the price they go for on Ebay. So I might try to sell it on Ebay instead... 

But well. I have run out of luck. There is just no money to be made with these things, can't find parts, and when you can it still doesn't make any financial sense to buy them...
So I got rid of an entire pile of them. All those that were not economically repairable, ie all of them...
Salvage all the circuit boards of course, a box full of them now, and scrapped the rest.
Makes for some much needed room.

So other the CD824 which I will sell one way or another, those that are left I am going to keep I think. Still, that's half a dozen of them ! 

- Philips CDC 486 6 disc changer, of course, since that's my youth/family player, that I fixed for my dad last X-mas and that he gave to me. It's my daily driver that plays every morning when I shower and every time I work at the bench.

- Another of the same : stumbled upon it, 50 Euros, like new, lower miles than mine, works perfectly and even came with the original remote. Dad lost our one. So that's super. So I bought that one for parts, to make sure I can keep mine going for a long time.

- My two old rebranded Philips CDM11/4 + TDA 1541A : the Radiola  CD371 and the Toshiba XR-9128.

Then a couple outsider that I may keep or  not in the long term, but will keep for now :

- Technics SL-PJ25 (non working) because of its cool and exotic engineering : its linear pickup motor, and its robustness, built like a tank.

- Thomson LD300 (non-working). Again luck of the draw. Found it cute and looked weird at the front. Looked more like an industrial or professional bit of kit than a consumer grade device... though I am sure it's consumer stuff... I guess. Upon receiving it, that impression was reinforced. Weights a ton despite it's small size, and the back of the unit tells you about the power and wavelength of the laser inside with a big yellow "caution" pictogram... I have yet to see a consumer player that tells you about the wave lenght of the laser inside...
IIRC when I powered it up, didn't work and display was showing garbage. Popped the hood to have a quick look. Found that there was a massive crack/physical damage to the main board ! So obviously many traces must be broken...  So this player is also a little challenge : can I manage to fix the circuit board ? Can I fix this player ?...
Will give it a try. if I fail it will probably end up being scrapped like all the others...

So now all I needed to be done with my CD player saga, was to button up the little Radiola so I don't have tons of parts spread all over the shelves, so I can frees some space and tidy things up in the lab.
I did buy the big DI shift register chip and proto board to try and play with that, see if I could revive the LED display. But I gave up on that. Too much other stuff to do, I am moving on. So I ordered the turn-key replacement you pointed me to on Ebay. 37.5 Euros shipped. Just received it today.
Well made. doesn't use the MM54XX big shift register though. Instead the guy used an 8 micro an Atmel AVR and a couple standard shift registers to assit it. He mus be programming them in situ because you can clearly se the foot print for the programming header...

Soldered it, works just fine now, except for the discrete LED corresponding to the " REPEAT "button, which refused to light up. I have not bothered to probe around to see whether the diode had failed or if the module was at fault, because I had more pressing matters to deal with : tried playing a CD. Worked at first... for 10 seconds, then stopped. Works erratically. Sometimes detects teh CD, sometimes not... well you get the picture, same as before.
I tried tweaking the laser trimmer but it was already to the max. I remember now... the player used to work only when the trimmer was at 99M. 100% would not work, 98% neither...so you just had to fart it to stop working.
Now I remember I swapped swing arms with the Toshiba and we concluded it was not the swing arm at fault, IIRC.... so I tried swapping the swing arm from a CDM4/19 IIRC. Can't remember what was the outcome, was so long ago.

Anyway this player doesn't work so I wasted 37.5 Euros on that display module. I am done with it, lost patience, moving on.
Well I will keep it anyway, can't sell it like that, or for so little money it's not work it. Plus I grew fond of it anyway...
So I think I will keep it for parts and am thinking of "upgrading", to a CD400 series, it's bigger brother, the one you've got and modified. IIRC I saw one that had a retractable keypad you can use to key in the track number you want and jump straight to it. I like this feature a lot as it's a pain otherwise to to " long jumps " so to speak.  So one day might get one of these players.

Anyway, thanks chaps for teaching me about CD players, learned a lot it was fun.

Think I am done with trying to repair consumer stuff, it's waste of time and no money to be made. I woud still do it to fix my OWN stuff of course, or have a QUICK look at stuff friends bring me, but no more.

For example I would like to find me a nice amp to go with my CD player. Following Shakal's advice I bough the cheapest broken half decent amp I could find, that bottom of the barrel Sony, for 15 Euros shipped... and it does the job.  But now I would like something nicer. Better quality front panel/controls/plastics, more stuff inside : Sony is pretty much empty... just a single chip STK design... wold like one with a nice toroïdal transformer and lots of power output transistors....
Don't know about brands models so might look for an old Yamaha "natural sound", and go from there. Of course a defective unit for 30 Euros max ! 

Anyway. Gonna give that little Thomson a quick go then that will be the end of my journey in CD player land. Was fun, I don't regret it...