Any docs for CDM4/31?

Does anyone know something about cdm4? i can´t find the doc in the net, is it DSA compatible? How to send commands to it? It´s really cheap (7€) and for experiments i consider it better than using my CD PRO2 because of damage risk. What kind of connectors are on this unit?
 

Attachments

  • g630097.jpg
    g630097.jpg
    16.8 KB · Views: 2,941
Disabled Account
Joined 2002
Hi Till, the picture is of a CDM2 if I'm correct. Can't answer your questons but can you obtain CDM4's ? If so I would be very happy to buy some ( 5 or 10 when possible ) because they are obsolete for years here. They are IMO one of the best transports ever made. They play CDR too ! I will send you a private mail about this, OK ?

Regards,

Jean-Paul
 
jean-paul,

which cdm4 is the one thats prefered?


cdm4-31?
An externally hosted image should be here but it was not working when we last tested it.

An externally hosted image should be here but it was not working when we last tested it.



cdm4-d36?
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.



cdm4-19?


An externally hosted image should be here but it was not working when we last tested it.


/kasra
 
Disabled Account
Joined 2002
It depends on what you want to do with it really. They all share the same laser as far as I know. For replacement purposes the CDM4/19 is most common. It is used in a lot of Philips/Marantz machines. Too bad that there is not much documentation to find on the web about these lasers / mechanics. They deserve better.

The cdm4-d36 looks best, it is the professional version as used in cd manufacturing test machines. Never seen one for real, only pics. Don't know anything more about that one.

CDM4/31 is to my knowledge a low budget version for HiFi sets but I could be wrong.
 
What's new?
The No.31.5's transport mechanism is mounted on the same sprung 12-lb lead-brick assembly as in the '31. However, whereas the No.31 used the Philips CDM 4 CD player mechanism, with its familiar swing-arm laser pickup, the '31.5 features Philips' new CDM 12 2x-speed industrial CD-ROM mechanism with a linear-tracking pickup and a digital servo. Because this is a CD-ROM drive, it won't by itself access the audio disc's subcode and index information. Madrigal therefore developed their own control software.

from
http://www.stereophile.com/showarchives.cgi?356

If you want a state of the art professional drive, i´m sure CD PRO2 is better. But at this price the CDM4/31 is a nice toy to play around with.
http://www.blackpudding.fsnet.co.uk/digital_jitter/laser_cross_reference.htm
 
I recived some of these CDM4/31.

The units seem to be unused, there is a plastic shield on the top to protect the laser. I can´t test it right now because i don´t know what kind of connector is on the PCB and what commands to control the CDP are needed.
 

Attachments

  • cdm4.jpg
    cdm4.jpg
    32.6 KB · Views: 2,494
There is one sign CDM4/31
3104 108 76231
8920 AH E-43611

There is one 5 Pin and one 14 Pin Connector on the PCB.

I see a 20 Pin TDA5709, 8Pin 4560D JRC 1347J, one TCA 0372DP2, one 28Pin TDA 5708, and some Transdistors and passive devices.
 

Attachments

  • cdm4b.jpg
    cdm4b.jpg
    27.8 KB · Views: 2,054
Till,

On the PCB is just the laser and radial control and some opamps to drive the transport. To get things working you need to decode the data (SAA7210/7310 decoder) and a microprocessor which reads the decoders subcode output and drives the radial control again. (doing this at work, so from memory).

In short, you need a philips cd player.... So it is not complete transport like your cd pro2 (which should have the decoder and micro, i2s out).

And i would also be interested in buying one or two of those..
See hasselt on the drive, the factory has just been closed....

Greetings,
GuidoB
 
The price was 7€ without any shipping cost etc. But i have only 8 ordered, 5 are promised to jean-paul. At least 2 i want for myself and the dealer (Pollin) has at the moment only 3 left. They also hav cheap alps rotary encoders(0,45€) or LCD ´s:

Anybody who could teach me what i need im addition to a mikrocontroller (PIC) to build a CDP with this CDM?

If we need this additional 3 pcs or something else, let me know asap so we could make a second order.
 

Attachments

  • g240246.jpg
    g240246.jpg
    7.8 KB · Views: 1,858
Had a chat tonight with a chap that worked at philips in hasselt.
I (we?) can forget to use a different model of cdm inside a player which originally contains an other cdm type. The processor's program contains the physical parameters of a cdm. Seems they have different resonance freqs etc.... So my search for a dead/cheap micromega trio mk1, meta research,studer 226 or krell goes on.

So apart from this cdm you need a decoder and some small stuff around it (check out a schematic of a player with the same cdm) and indeed a programmed micro. But i guess the only guy to teach you would be somebody who worked on these drives. Any belgians on the forum..?

Best way forward, i is to find nice broken and therefore cheap player which you can then give a new cdm and then tweak it. Think that's why the others (and myself) would like to have one.

Or find a source for a cdm9 (pro). Best one around (?) and it contains the decoder and micro on the attached pcb. There you need to 'talk' to it in some kind of command language and i might be able to get info on that.

Good luck!
Guido