Anyone with a dead Philips CDM-X mech they want to resurrect?

[amc184]

Recently I've been looking into replacing the laser diodes in the aging Philips CDM-0 to CDM-9 series CD mechanisms. I found that all the radial armed mechs, right from the first generation CDM-0 of the early eighties to the end of the line CDM-9 of the nineties, used the same laser diode. I was surprised, I kind of expected to see a change over the fifteen or so years these mechs were around.

Anyway; I managed to get hold of a bunch of brand new laser diodes of the same brand and model, complete with 'bling bling' gold cases. However, I don't have any suitable candidate mechs at the moment, so:

Does any of you out there have a tired old CDM-0, CDM-1, CDM-2 or CDM-3 which you want to have an new lease on life?

I'm interested in replacing the laser diode on mechs where:
- The laser is truly worn out, not the electrolytic capacitors in the player. Too many times the laser is blamed when it is the servo's fault.
- The mech has been treated properly (especially in regards to static precautions). Static discharge destroys photodiodes, there is no way to rescue a static damaged mech.

I essence, I'm looking for mechs where the laser is at fault, not something else.

I'm offering this for free, hopefully there are a few people out there that are keen and have mechs that fit the above criteria. I'm quite excited about this experiment, as if it is successful, we could get a lot more life out of the radial armed mechs yet!

I'm only keen on trying the earlier variants at the moment (CDM-0 to CDM-3), the later variants are more compact, and I don't even think the diode is replaceable for some CDM-4s, due to the construction techniques used.

[Mooly]

I wish you good luck with your venture. That laser diode (The Sharp LTO22MC) was used in many machines, early Sony's etc too.
I suspect you may well get some to work, but that "fine tuning" of the absolute placement of the diode may well be problamatic and require careful monitoring of the RF and error signals.
Good luck with it

[amc184]

I don't think diode placement will be too much of a problem. If you look at the tolerances of the diode itself, and the way that they are installed into the RAFOC body, you will see what I mean.

I wasn't aware that some Sony mechs used this diode, care to mention which ones?


So, any takers?

[Mooly]

"I wasn't aware that some Sony mechs used this diode, care to mention which ones?"

It's a long time ago I used to remove old laser diodes to play with from optical blocks that we replaced... still have odd ones kicking around. KSS110? from the D50mk1 portable maybe. They were from KSSxxx pickups as I remember.
It will be really interesting to see if it works, I had often wondered the same about the diode in the CDM12.4 and so on, easily removed, just glued in place.
Also wonder how much "internal contamination" of the rest of the optics is to blame for many problems.

[tiefbassuebertr]

Unlike the Sony laser diodes from the most optical pick up's from KSS series of those units in the CDM Philips drives are considerably less frequently responsible for failures. I have watched such faulty Sharp laser diodes only rarely and have replaced them by a version from ROHM (RLD78), what I have done without problems.
From the CDM-9, however, no longer 3-lead diode was used, instead of this a new development from Sharp - a hologram laser diode (with integrated OPIC)
please look at follow datasheet:
http://www.datasheetcatalog.org/data...rp/mXqxuqy.pdf
additional informations about the weblink
http://www.patentstorm.us/patents/5511059.html

From the successor of CDM 9, the CDM 12, the newer types from Sharp LT0H30PA, LT0H30PB, LT0H30PC (mentioned in US patent 5511059) was used. Unfortunately there are no datasheet, only this informations:
http://www.datasheets.org.uk/search....b.x=43&sub.y=8.
At this type I am interested and also to the successors of the Sony laser diodes from Sony KSS-272A and KSS-273A to perform a replace of the faulty diode. Because the KSS272A and KSS273A are no longer available, this is the only possibility. For further details about this you can more read on the following threads that I opened in this cases:
Laser Diode Successor of SLD-104U for SONY ESPRIT KSS Series 179
http://www.diyaudio.com/forums/searc...0&pp=25&page=4
Databook about SONY's KSS optical pick up series 163
Databook about SONY's KSS optical pick up series
new Brand of Hologram Laser (LDGU) LT0H30PA inside by Philips CDM12 and VAM12 mech 270
new Brand of Hologram Laser (LDGU) LT0H30PA inside by Philips CDM12 and VAM12 mech
dig out (S/P-DIF, DOBM) for Philips CD100 and Revox B225 (only SAA7000 data out)
VAM1204 VAM1205 VAM1206 VAM1250 VAM1252 VAM1254 CDM12pro VAU1254=CDM12.4 compatib 476

Best thanks for additional advices

[restorer-john]

How about a Kyocera (Akai CDD1) laser head- it uses the same sharp LD- true first generation machine Japanese made but with TDA1540Ds x2 and 4x.
Wanna do that one for me Bro?

[amc184]

@ tiefbassuebertr:

Wow, you have quite a lot of knowledge on the subject. To be honest, nothing that Philips made after the CDM-9 interests me. The quality just isn't there.

@ restorer-john:

Sure, I'll give it a try. Email me and we'll set up the details. Nice CD player too, there's not that many first generation units still around. I've got a Philips CD202 myself, still plays perfectly, CDRs included.

[tiefbassuebertr]

@ restorer-john:

the optical pick up, what you need, was manufactured from the follow three brands:
1) NEC HLPL 030010
(no informations online, see jpg attachement)
2) Toshiba OPH-31 (no informations online)
3) Olympus TAOHS informations about follow weblinks:
http://www.olympus-global.com/en/cor...chron/1960.cfm (see 1980-1984)
http://www.aomori.olympus.co.jp/en/company/history.html (see 1988)
http://www.okaya.olympus.co.jp/jp/introduction/ (see 1986)
http://translate.google.de/translate...hl=de&ie=UTF-8
http://books.google.de/books?id=zNmn...OHS%22&f=false

This optical pick up was inside by the follow first generation models:

Universum AD2000
TENSAI TAD-2000
ROTEL RCD-870
PHASE LINEAR 9500
MICRO CD-M1
KYOCERA DA-01
Kenwood L03DP (L-03 DP service Manual printed in japanese from 1982)
ClairTone 2704
BETA LASER ADD 200
AKAI CD-D1 (CDD01)

As I know, the type of the used laser diode you can find in the service manuals but it is hard to believe for me, that the reason for errors at your device is really the diode itself. In most cases there are other reasons.

[restorer-john]

I actually have two CDD1s I have collected and they both exhibit the same gradual deterioration until they are essentially emitting nothing. One machine was given a complete alignment (that took nearly a day!- have look at the service manual!) and after it performed no better (much to my annoyance). Anyway, after 4 years in boxes, neither of them work now and I cannot detect any laser emission with my homemade LPM. I therefore concluded it was the LD. I am hesitant to remove the LD until I can confirm it is indeed Sharp LD- but I'm pretty sure it is. After all, I have nothing to lose at this point if the LD is indeed dead.

[amc184]

This is exactly the sort of mech I am looking to use. Slow deterioration of performance, and nothing to lose. Only one question, have you replaced the electrolytic capacitors in the servo section, or the whole player for that matter? If not, that's probably your problem.

On a side note (I started this thread, I can go slightly off topic), has anyone else noticed how stupidly CDM-2s are labeled?

If you have a CDM-4/19, and want to replace it, just get any other CDM-4/19. But, if you've got a CDM-2/10, and you get another CDM-2/10, you can go very wrong. You have to go off of the four digit product code suffixes. Why, Philips, why?

Heres an example, using photos (some are my own, some from elsewhere on the web):

1) CDM-2 0008 labeled as a CDM-2/10
2) CDM-2 0008 labeled as a CDM-2/29
3) CDM-2 0300 labeled as a CDM-2/10
4) CDM-2 0300 labeled as a CDM-2/29

You would assume (1) and (3), the 2/10s, and (2) and (4), the 2/29s are the same, but they're not.