Mechanical alignment is a huge problem as it can't be tweaked with the thing playing.
Knowing what we know now about the CDM12.4, I wish I saved all the "faulty" ones that techs replaced routinely.
Maybe an old player (like the Micromegas) that's original but being sold cheaply as faulty would be the best way to get a pickup that could be refurbished... as it was the grease issue that was the main problem with the originals.
Knowing what we know now about the CDM12.4, I wish I saved all the "faulty" ones that techs replaced routinely.
Maybe an old player (like the Micromegas) that's original but being sold cheaply as faulty would be the best way to get a pickup that could be refurbished... as it was the grease issue that was the main problem with the originals.
This is indeed currently the only way, because nobody can tell me until this day the currently producer of the hologram laser diodes used still in currently available VAM1254/VAU1254 mechanism.
If I know a guy, whose mother language is Japanese or Chinese, and could perform for me some phone calls in China or Japan in this matter, I had figured out it certainly quickly. Correspondence in the english language with far east employers is very difficult.
Unfortunately the most diyaudio members from far east written here mostly their questions to get informations so as offers about their products, but don't written here for the dissemination resp. transmission of intresting informations from there
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This is one of the most important question for me. Therefore I have start this thread:
http://www.diyaudio.com/forums/digi...lt0h30pa-inside-philips-cdm12-vam12-mech.html
I am still looking for such parts in highest quality, highest reliability and longest life time.
Who are the currently manufacturer of this devices?
new advices at post #8 about
http://www.diyaudio.com/forums/digi...se-replacement-laser-problem.html#post4049904
http://www.diyaudio.com/forums/digi...se-replacement-laser-problem.html#post4049904
Reviving an old thread....
I tripped across this while searching for a solution to the NON working pickups on ebay.
I have a B&O unit with a 12.4 mech in it which did not read at all. So I tried the new pickup route. This "worked", but very poorly. Finally, figuring I have nothing to loose, I took apart the old pickup and sure enough... it was filthy. I do small electronics repair and have a stereo microscope to work with. After cleaning the optics and re-assembling the pickup, IT WORKED!!!
Not only that, it works PERFECTLY! CDR's included.
Really thankful to whomever came up with this. It saved my Beosound 4000, as the aftermarket pickups appear to be garbage.
THANKS!!!
I tripped across this while searching for a solution to the NON working pickups on ebay.
I have a B&O unit with a 12.4 mech in it which did not read at all. So I tried the new pickup route. This "worked", but very poorly. Finally, figuring I have nothing to loose, I took apart the old pickup and sure enough... it was filthy. I do small electronics repair and have a stereo microscope to work with. After cleaning the optics and re-assembling the pickup, IT WORKED!!!
Not only that, it works PERFECTLY! CDR's included.
Really thankful to whomever came up with this. It saved my Beosound 4000, as the aftermarket pickups appear to be garbage.
THANKS!!!
That's greatreally pleased to hear you have been successful with this.
Yes, thanks!
I am a self taught expert on the swing arm CDM's and love them! So I tend to just avoid CD players that were updated to the CDM-12. I know they die and are a pain to find a good one. But I may re-think picking up a dead unit with a CDM-12 now. I love the Beocenter 9500 for example, but passed on the "upgraded" one's in the past just because of the laser unit in it.
The swing arm units? Never had one I could not fix. Fantastic pickups.
Hi, I have a general questions regarding Philips laser pickups:
a) how to take out a pickup from laser mechanism (VAM) - the pickup is on a metal stick which is fixed on both sides with a white plastic endings - do you have to use force to take them out or there is a trick ?
b) how to take out the metal shield covering laser diode connections or other ic connections - is it screwed or mounted with some resin/glue ?
I am asking this because my VAM 1250 needs some time to "warm up" so maybe some joints have to be resoldered.
a) how to take out a pickup from laser mechanism (VAM) - the pickup is on a metal stick which is fixed on both sides with a white plastic endings - do you have to use force to take them out or there is a trick ?
b) how to take out the metal shield covering laser diode connections or other ic connections - is it screwed or mounted with some resin/glue ?
I am asking this because my VAM 1250 needs some time to "warm up" so maybe some joints have to be resoldered.
Everything just clips together. You normally remove the gears to leave the pickup free to move, and then release the chromed rail... I would have to have one in front of me to recall exactly what the fittings are like... but its a seconds job to release them.
The metal cover will be soldered to the flexiprint. I have never had dries on any Philips pickups that I can recall.
The metal cover will be soldered to the flexiprint. I have never had dries on any Philips pickups that I can recall.
Based on your experience with no dries on Philips pickup and first chinese attachment to post #11 (Google translation) it seems that warming up problem is known by Chinese people and they propose a hair dryer to solve it. However I can't determine how exactly as the translation is not fully understandable. Could you be so kind and help ?
The link doesn't work any more and the pdf's are non understandable when I try and translate them using an MS app. All the right words (maybe 
) but definitely not in the right or meaningful order.
I've no idea what they are on about and what a hairdryer is used for. The only thing I could think of would be soften the adhesive holding the diode in place although I found a good determined 'twist' with suitable pliers holding the laser diode PCB will crack the adhesive and break the seal.
) but definitely not in the right or meaningful order.I've no idea what they are on about and what a hairdryer is used for. The only thing I could think of would be soften the adhesive holding the diode in place although I found a good determined 'twist' with suitable pliers holding the laser diode PCB will crack the adhesive and break the seal.
Please let me provide the translation ( I should have done it in my previous reply, sorry):
Philips circular laser head cold machine does not read the disc,
the thermal machine disc; objective diffuse dark red spot and the disc does not rotate; reading disc pauses or mosaics; can not read CD discs and so on a series of failures is Completely repairable
【Failure a cold machine does not read the disc, heat machine disc reading
【Reason】
⒈ circular laser holographic mirror, the mirror mirror and the objective mirror is atomized;
⒉ laser head movable arm power arm ("elastomer" hinge) is a two-dimensional molded plastic parts, due to long-term frequent movement Fatigue and deformation, the cooler beyond the focus / tracking servo control range, the engine heat distortion results barely able to error control.
[Method one] for the reason ⒈
available hair dryer to blow the laser head inside or the surface of the fog, and can be placed in the machine or below the desiccant to prevent the fog when the cold again hit the laser head of the mirror and a cold mirror Failure to read the disc
【Method 2】 For the reason ⒉
remove the movable part of the 〔〕 〔the end of the lens holder bracket〕 two fine-tuning screw sealant, and then with the eye flat on the surface of the objective lens, adjust the two fine-tuning screws, longitudinal and objective objective lens surface should be with Black pedestal vertical and horizontal plane parallel to reach the "mirror vertical flat base longitudinal mirror cross horizontal flat horizontal" so far, as shown in Figure ⒈ (click to enlarge):
【Method three】 It is best to replace a "chrome day" CN1201 / 12 laser head, immediately solve this problem completely.
As I am neither "laserologist" nor specialist in tech English - could you find out what they mean to be done in simple and comprehensive language ?
Philips circular laser head cold machine does not read the disc,
the thermal machine disc; objective diffuse dark red spot and the disc does not rotate; reading disc pauses or mosaics; can not read CD discs and so on a series of failures is Completely repairable
【Failure a cold machine does not read the disc, heat machine disc reading
【Reason】
⒈ circular laser holographic mirror, the mirror mirror and the objective mirror is atomized;
⒉ laser head movable arm power arm ("elastomer" hinge) is a two-dimensional molded plastic parts, due to long-term frequent movement Fatigue and deformation, the cooler beyond the focus / tracking servo control range, the engine heat distortion results barely able to error control.
[Method one] for the reason ⒈
available hair dryer to blow the laser head inside or the surface of the fog, and can be placed in the machine or below the desiccant to prevent the fog when the cold again hit the laser head of the mirror and a cold mirror Failure to read the disc
【Method 2】 For the reason ⒉
remove the movable part of the 〔〕 〔the end of the lens holder bracket〕 two fine-tuning screw sealant, and then with the eye flat on the surface of the objective lens, adjust the two fine-tuning screws, longitudinal and objective objective lens surface should be with Black pedestal vertical and horizontal plane parallel to reach the "mirror vertical flat base longitudinal mirror cross horizontal flat horizontal" so far, as shown in Figure ⒈ (click to enlarge):
【Method three】 It is best to replace a "chrome day" CN1201 / 12 laser head, immediately solve this problem completely.
As I am neither "laserologist" nor specialist in tech English - could you find out what they mean to be done in simple and comprehensive language ?
Best guess...
Reason 1. The internal optics are fogged. Sony issued a technical bulletin (for their pickups) many years ago saying that the lens coating was hygroscopic and could absorb moisture giving a cloudy look to the lens. Maybe they mean something similar here. The optics can be 'restored' by heating and drying.
Reason 2. The lens suspension is just plastic material and can change its characteristics over time as the material constantly flexes when playing a disc.
When the pickup is warm, the material changes its 'stiffness' and this enables the servo to work and lock correctly.
Are they saying that to 'fix' this you can alter the height of the lens base assembly by tweaking the alignment screw and by using visible reflections on the lens surface to keep it aligned with the mirror below.
(lens suspension failure (or a change in the characteristics) was an issue with some Sony pickups many years ago... and the fix was always to replace the pickup, not to try and fiddle the issue)
---------------------------------------------------
What I can tell you is that all pickups are precisely adjusted during manufacture and they really are precision optical instruments. All this sounds like a fudge and fiddle that might enable some pickups with certain issues to operate at a basic level. The bottom line is that when you are resorting to things like this then you really are in the last chance saloon for getting it to operate.
By all means experiment... if you have nothing to loose then you just might have everything to gain. Just don't be disappointed if it doesn't work or if it ends up worse than it is now.
Reason 1. The internal optics are fogged. Sony issued a technical bulletin (for their pickups) many years ago saying that the lens coating was hygroscopic and could absorb moisture giving a cloudy look to the lens. Maybe they mean something similar here. The optics can be 'restored' by heating and drying.
Reason 2. The lens suspension is just plastic material and can change its characteristics over time as the material constantly flexes when playing a disc.
When the pickup is warm, the material changes its 'stiffness' and this enables the servo to work and lock correctly.
Are they saying that to 'fix' this you can alter the height of the lens base assembly by tweaking the alignment screw and by using visible reflections on the lens surface to keep it aligned with the mirror below.
(lens suspension failure (or a change in the characteristics) was an issue with some Sony pickups many years ago... and the fix was always to replace the pickup, not to try and fiddle the issue)
---------------------------------------------------
What I can tell you is that all pickups are precisely adjusted during manufacture and they really are precision optical instruments. All this sounds like a fudge and fiddle that might enable some pickups with certain issues to operate at a basic level. The bottom line is that when you are resorting to things like this then you really are in the last chance saloon for getting it to operate.
By all means experiment... if you have nothing to loose then you just might have everything to gain. Just don't be disappointed if it doesn't work or if it ends up worse than it is now.
Mooly, great thanks for explanation !
I have Beosound 9000 with VAM 1250. I have just replaced the same VAM from Marantz DR4050 and works OK. I have the "old" VAM with warming up problem as a backup.(I had to go from one disk to another to start operation and with 5th or 6th disk it started to play but then it should play the disk to the end to be sure that all next disks are played normally). In a free time, as a hobby I thought to try to fix it by resoldering all joints, however I should desolder the metal shield and solder it back at the end as without it the pickup may work badly - is it true ?
So generally - what do you suggest me to do ? do something... or live it as it is and be happy to have a backup pickup able to play after warming up.
I have Beosound 9000 with VAM 1250. I have just replaced the same VAM from Marantz DR4050 and works OK. I have the "old" VAM with warming up problem as a backup.(I had to go from one disk to another to start operation and with 5th or 6th disk it started to play but then it should play the disk to the end to be sure that all next disks are played normally). In a free time, as a hobby I thought to try to fix it by resoldering all joints, however I should desolder the metal shield and solder it back at the end as without it the pickup may work badly - is it true ?
So generally - what do you suggest me to do ? do something... or live it as it is and be happy to have a backup pickup able to play after warming up.
If you like the player this much then I would try and get a second spare pickup of known good quality... which may not be easy.
The metal shield should come off in seconds if you want to play with it. Yes, its probably quite important that it is refitted as it shields the high impedance points of the laser diode from noise. Without it and the RF signal will look very noisy on a scope, and that will add to the playability problems.
The metal shield should come off in seconds if you want to play with it. Yes, its probably quite important that it is refitted as it shields the high impedance points of the laser diode from noise. Without it and the RF signal will look very noisy on a scope, and that will add to the playability problems.