The laser arm does this during the tests
Test 1
Press >> arm swings fully out
Press << arm swings fully in
Put CD on spindle
Test 2 - Press Advance looks for focus; display gives 02 message
Test 3 - Press Advance and discs spins; display gives 0.3 message
Test 4 - Press Advance again and test fails with F4 message
For test 2, 3 and 4 the arm does not appear to move again from its test 1 << swing in position.
Test 1
Press >> arm swings fully out
Press << arm swings fully in
Put CD on spindle
Test 2 - Press Advance looks for focus; display gives 02 message
Test 3 - Press Advance and discs spins; display gives 0.3 message
Test 4 - Press Advance again and test fails with F4 message
For test 2, 3 and 4 the arm does not appear to move again from its test 1 << swing in position.
Quick update - I haven't tried the connector 31 measurements yet.
But, I did remove the CD mechanism, cleaned up the ends of the ribbon cable, placed the mechanism on top of the chassis, ran the test program and it passed all of test 4 for the radial arm. It span up, and pressing << and >> moved the laser assembly in and out. Success 😀😀😀 Once only 🙁🙁🙁🙁🙁🙁🙁
After that it went back to failing test 4 even after I took it apart again, reassembled it and placed it back in its correct place in the metal chassis.
I'll try the electrical tests later this week but I'm really at a loss as to the problem other than a failed radial assembly.
But, I did remove the CD mechanism, cleaned up the ends of the ribbon cable, placed the mechanism on top of the chassis, ran the test program and it passed all of test 4 for the radial arm. It span up, and pressing << and >> moved the laser assembly in and out. Success 😀😀😀 Once only 🙁🙁🙁🙁🙁🙁🙁
After that it went back to failing test 4 even after I took it apart again, reassembled it and placed it back in its correct place in the metal chassis.
I'll try the electrical tests later this week but I'm really at a loss as to the problem other than a failed radial assembly.
Nick, I understand your frustrations, from this point on I guess you have tried the very best you could do. Electronics that operates one moment and fails the next is a dramatic thing. There is no such thing as a selfrestoring semiconductor. Your problem must be caused by a mechanical defect. Poor connection, friction, position etc. Give it a shake and bake and use the freeze spray. Play it in different positions. No result? Find a donor CD drive😢
What is this component on the radial control/laser assembly? I thought it might be a resistor, but it only reads about 2 ohms, admittedly in circuit. If tested as a capacitor it tests open, with leads both ways around.
Nick, I am just as puzzled as you are. Recommend you study chapter 9-1 of the service manual. It shows the 3 SMD components on the laser assembly. It shall have a resistor of 1K, an inductor, and a capacitor. You will have to probe which is what.when you measure 2 ohms in both directions you may be across the inductance. Try to measure from ground at P31 pin 10 and 9.
I took apart the laser radial mechanism, lubricated the ball bearings as shown in the Philips manual, reassembled and it passed all the tests. I performed the tests with the CDM2/10 sitting on top of the rubber mounting bushes.
With the CDM2/10 assembly still sitting on the bushes I tried to play a few CDs. One was read OK and seemed to play. I say seemed to play as the display showed total length of the CD and the number of tracks but only showed 0:00 when the track was playing. This may be because the unit wasn't fully assembled and some grounding wires were not connected. I also don't know if it actually produced any sound as it was not plugged into the Beomaster.
But, it would only do this for 1 CD regularly and on occasions another CD. It would also take a long time to read the TOC before it recognised the CD. Then after leaving it for a few hours it refused to play any CD and when I put back into test mode it wouldn't pass the radial assembly test.
I took it apart again lubricated the bearings again and it was a repeat of the above. I think the bearings are drying out so I'm thinking of getting some silicone oil. At the moment I've used the same general purpose oil in a precision lubricator I used to lubricate the tape deck when I was working on that. I'm not sure if silicon oil would be different, but that is what it asks for so no harm in trying.
To conclude, I'll try the silicone oil and if that doesn't work I'm going to look for a working CD player with a CDM2/10 in it on eBay and see if I can pick it up for not much money. I don't see why it has to be a B&O player, but happy to be corrected. No doubt it'll be a hunt, but hey ho it's a hobby 😀 😀
With the CDM2/10 assembly still sitting on the bushes I tried to play a few CDs. One was read OK and seemed to play. I say seemed to play as the display showed total length of the CD and the number of tracks but only showed 0:00 when the track was playing. This may be because the unit wasn't fully assembled and some grounding wires were not connected. I also don't know if it actually produced any sound as it was not plugged into the Beomaster.
But, it would only do this for 1 CD regularly and on occasions another CD. It would also take a long time to read the TOC before it recognised the CD. Then after leaving it for a few hours it refused to play any CD and when I put back into test mode it wouldn't pass the radial assembly test.
I took it apart again lubricated the bearings again and it was a repeat of the above. I think the bearings are drying out so I'm thinking of getting some silicone oil. At the moment I've used the same general purpose oil in a precision lubricator I used to lubricate the tape deck when I was working on that. I'm not sure if silicon oil would be different, but that is what it asks for so no harm in trying.
To conclude, I'll try the silicone oil and if that doesn't work I'm going to look for a working CD player with a CDM2/10 in it on eBay and see if I can pick it up for not much money. I don't see why it has to be a B&O player, but happy to be corrected. No doubt it'll be a hunt, but hey ho it's a hobby 😀 😀
Nick, you will be known as the expert into disassemble/reassemble the CD drive of this B&O CD3300.
When you finally gave up, why not try tweaking the focus offset potmeter R3146?
Measure the Ohmic value or note the wiper position and give it some adjustment up and check disc tracking. If the result is worse turn it into a small down direction. When you introduce too much offset the disc maybe scratching the laser head. When no improvements noted set the R3146 back to the original position and enjoy the rest of the day…
When you finally gave up, why not try tweaking the focus offset potmeter R3146?
Measure the Ohmic value or note the wiper position and give it some adjustment up and check disc tracking. If the result is worse turn it into a small down direction. When you introduce too much offset the disc maybe scratching the laser head. When no improvements noted set the R3146 back to the original position and enjoy the rest of the day…
I'm not jumping with joy yet but it LIVES 😀😀😀 but not all the time 🙁 🙁.
Some CDs don't play correctly. They have glitches during playback as if the player's error correction isn't fully working correctly. These CDs work fine on my main CD player. Plus, the glitches aren't always in the same place. Perversely some CDs play without any errors at all.
I think correct lubrication of the radial arm as shown in the service manual is the answer. And probably has been since I dug it out the attic after storing it there for 10 years. I've just used mineral oil, but the service book says silicone oil. Is there much difference?
As I forgot to put in the triangular perforated piece of plastic, I need to take it apart again. I'll use that opportunity to put a little more lubrication on the ball bearing to see if it helps.
Finally, I checked the voltages mentioned in the service manuals but these were pretty much correct.
Some CDs don't play correctly. They have glitches during playback as if the player's error correction isn't fully working correctly. These CDs work fine on my main CD player. Plus, the glitches aren't always in the same place. Perversely some CDs play without any errors at all.
I think correct lubrication of the radial arm as shown in the service manual is the answer. And probably has been since I dug it out the attic after storing it there for 10 years. I've just used mineral oil, but the service book says silicone oil. Is there much difference?
As I forgot to put in the triangular perforated piece of plastic, I need to take it apart again. I'll use that opportunity to put a little more lubrication on the ball bearing to see if it helps.
Finally, I checked the voltages mentioned in the service manuals but these were pretty much correct.
Hi
Sorry for partly hijacking this thread.
I have almost the exact same trouble on a Bang&Olufsen Beocenter 9000 which i believe has the CDM4/33 unit. At least it looks quite similar to the manual for it and to the unt you are trying to repair here...
My unit fails the 4th testmode, and is always going to the innermost position, but the radial motor test fails (with a F.4 error on the display). If it is powered off the laser unit return to the middle position, and is easily bumped around if i try.
I've measured many of the same signals as is mentioned earlier in this post, and also checked signals with a heap handheld oscilloscope. The R1 and R2 seems to react t me knocking on the radial motor, the amplitude of the signal increases with displacement. However, I am unable to pick up any signal on pin 7 of IC6302, the RE signal. It's supposed to be 650Hz, but i do not know the amplitude... Do anyone have a picture of how the signal is supposed to look like?
I've not tried any kind of power-injections yet.
Any suggestions of further troubleshooting is most welcome!
PS: I've recapped the electrolytic caps on both the servo and the decoder board to no help. The focus test also seems to pass fast and easily, display going from F.2 to 0.2 for the 2nd testmode.
Sorry for partly hijacking this thread.
I have almost the exact same trouble on a Bang&Olufsen Beocenter 9000 which i believe has the CDM4/33 unit. At least it looks quite similar to the manual for it and to the unt you are trying to repair here...
My unit fails the 4th testmode, and is always going to the innermost position, but the radial motor test fails (with a F.4 error on the display). If it is powered off the laser unit return to the middle position, and is easily bumped around if i try.
I've measured many of the same signals as is mentioned earlier in this post, and also checked signals with a heap handheld oscilloscope. The R1 and R2 seems to react t me knocking on the radial motor, the amplitude of the signal increases with displacement. However, I am unable to pick up any signal on pin 7 of IC6302, the RE signal. It's supposed to be 650Hz, but i do not know the amplitude... Do anyone have a picture of how the signal is supposed to look like?
I've not tried any kind of power-injections yet.
Any suggestions of further troubleshooting is most welcome!
PS: I've recapped the electrolytic caps on both the servo and the decoder board to no help. The focus test also seems to pass fast and easily, display going from F.2 to 0.2 for the 2nd testmode.
Welcome @Insectdium, to our B&O "nightmare" 🙂
The CD assembly in the CD3300 is a CDM 2/10 not, as you say, the CDM4/33 you have. But, having just looked at page 22 of the service manual for the CDM4/33 it does appear as if the radial assembly is similar to the CDM2/10.
To pass the F4 test I dismantled the radial assembly and then put a few drops of precision oil into the place the ball bearing fits, indicated by an "A in a diamond" in the manual. Both top and bottom. It then passed the test. When you take the radial assembly apart be very careful you don't dop the ball bearings. I first did it without benefit of the manual and nearly lost one as it just popped out.
As I posted previously my player still jumps so I'm going to take it apart again and this time see if I can put a very small amount of oil to lubricate the drive motor shaft. The service manual doesn't mention lubrication is needed, but the player is nearly 40 years old and was in my house's roof space for many years so any lubrication put there at manufacture may well have dried out.
The CD assembly in the CD3300 is a CDM 2/10 not, as you say, the CDM4/33 you have. But, having just looked at page 22 of the service manual for the CDM4/33 it does appear as if the radial assembly is similar to the CDM2/10.
To pass the F4 test I dismantled the radial assembly and then put a few drops of precision oil into the place the ball bearing fits, indicated by an "A in a diamond" in the manual. Both top and bottom. It then passed the test. When you take the radial assembly apart be very careful you don't dop the ball bearings. I first did it without benefit of the manual and nearly lost one as it just popped out.
As I posted previously my player still jumps so I'm going to take it apart again and this time see if I can put a very small amount of oil to lubricate the drive motor shaft. The service manual doesn't mention lubrication is needed, but the player is nearly 40 years old and was in my house's roof space for many years so any lubrication put there at manufacture may well have dried out.
Yes, the units is quite similar, and I'm not entirely sure it is a CDM4/33 I have, as there is small differences from mine to the only manual i found, its just the most similar I've found (it's for the Beocenter 9500) 🙄
I'm not so certain that my unit needs lubrication, it moves quite freely when not activated, ut the thing is, it moves to the innermost position and don't try to move outwards after that when doing test 4 (or regular play). If i nudge it it moves back to the innermost position. When CD is turned of, it moves back to center position.
I'm also unable to measure any reasonable signal for the RE signal. it is supposed to correct the arm movement, and should have a 650Hz embedded signal from the internal oscillator, so I was wondering if anyone have a picture of this signal for comparison...
It might be that the TDA5709 chip (IC6102) is busted, or some setup of it is wrong (tho, I have verified the power rails to it is correct alt least)
I'm not so certain that my unit needs lubrication, it moves quite freely when not activated, ut the thing is, it moves to the innermost position and don't try to move outwards after that when doing test 4 (or regular play). If i nudge it it moves back to the innermost position. When CD is turned of, it moves back to center position.
I'm also unable to measure any reasonable signal for the RE signal. it is supposed to correct the arm movement, and should have a 650Hz embedded signal from the internal oscillator, so I was wondering if anyone have a picture of this signal for comparison...
It might be that the TDA5709 chip (IC6102) is busted, or some setup of it is wrong (tho, I have verified the power rails to it is correct alt least)
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My radial arm moved very freely if I tapped it side to side with my finger. It also passed the stage 1 test when I pressed the fast forward and return buttons when it "flew" from side to side. But it was only after I lubricated it, it passed the stage 4 test.
Now, that might not be your problem, but it does needs lubrication according to the service book and I assume yours hasn't had any since it was sold over 30 years ago.
Electronic issues are nearly always recommended as the things to check first when repairing old hi-fi, and no doubt rightly so in most cases. But, I followed the same advice when I repaired my Beocord 3300 tape deck which had no sound from the left channel. The problem turned out to be a failed tape head. Something I was assured would not be the issue.
Now, that might not be your problem, but it does needs lubrication according to the service book and I assume yours hasn't had any since it was sold over 30 years ago.
Electronic issues are nearly always recommended as the things to check first when repairing old hi-fi, and no doubt rightly so in most cases. But, I followed the same advice when I repaired my Beocord 3300 tape deck which had no sound from the left channel. The problem turned out to be a failed tape head. Something I was assured would not be the issue.
Heh, yeah, it's not easy to find the culprit...
Had I seen any attempt from the system to move the laser head at all I would also go for the mechanical fix, and I might lubricate the unit in near future, but the service manual says it should be a 650Hz signal at the RE pin, and that one should check this signal if test 4 does not work. Also, if feels like the unit is not mechanically stuck, more electrically forced to go to this position only, and not track at all... Unfortunately, I can't find any button to press to move the head under testmode with my stereo system 😕
Question is, is the RE signal not there, or is it just me?
Also, the manual does not say what is assumed to be the fault if the signal is not there. That is what I had hoped someone had experience with 😀
(Also, this thread was the closest on the entire forum)
Had I seen any attempt from the system to move the laser head at all I would also go for the mechanical fix, and I might lubricate the unit in near future, but the service manual says it should be a 650Hz signal at the RE pin, and that one should check this signal if test 4 does not work. Also, if feels like the unit is not mechanically stuck, more electrically forced to go to this position only, and not track at all... Unfortunately, I can't find any button to press to move the head under testmode with my stereo system 😕
Question is, is the RE signal not there, or is it just me?
Also, the manual does not say what is assumed to be the fault if the signal is not there. That is what I had hoped someone had experience with 😀
(Also, this thread was the closest on the entire forum)
Ah!
After reading the manual a few more times i suddenly understood what testmode 5 and 6 was. It is the radial arm move on the beocenter units, just as you mentioned you, uknick, did with ffw and back buttons...
I did not quite understand the "skip ahead 64 tracks" the manual was talking about...
How huge step do your unit move for each of these button presses/steps?
Mine bangs the head at the uttemost extreme ends...
After reading the manual a few more times i suddenly understood what testmode 5 and 6 was. It is the radial arm move on the beocenter units, just as you mentioned you, uknick, did with ffw and back buttons...
I did not quite understand the "skip ahead 64 tracks" the manual was talking about...
How huge step do your unit move for each of these button presses/steps?
Mine bangs the head at the uttemost extreme ends...
So, I opened up the unit again and lubricated it. Made note of a sticker telling me the model name, a CDM-4/24.
The lubrication did not help out, still not able to read the TOC, but now at least i know the exact model name...
Anyone sitting on this models' specific service manual?
The lubrication did not help out, still not able to read the TOC, but now at least i know the exact model name...
Anyone sitting on this models' specific service manual?
Sorry to hear that @Insectdium
I assume you have the Beocentre 9500 service manual. I've just had a look at it and the test function for the CD appears to be slightly different to the CD3300.
On the CD3300 once in test mode we have;
Test mode 1 - tests the connection of the ribbon cable from the servo board to the radial arm. Pressing FFD >> or REV << swings the arm fully out (with some force) and then back again. There is no gradual movement. [I can't see this test in the 9500 book]
Test Mode 2 - does focus test [seems to be the same for the 9500]
Test Mode 3 - tests motor [seems to be the same for the 9500]
Test Mode 4 - tests radial search. In test mode 4 if you don't get the F4 error pressing the FFD >> or REV << gradually (by gradual I mean it will take several seconds of continual pressure on the >> to get to the end) moves the arm fully out and then back in again. [I assume this is your test mode 4, 5 and 6. For example, it says in the CD3300 book "press << and the Laser arm jumps backward across 64 tracks"]
With regard to help on the CDM4/24 have you seen this thread;
https://archivedforum2.beoworld.org/forums/t/35846.aspx?PageIndex=1
not sure if it'll help but it does go down the rabbit hole with regard to capacitor types on the servo board.
I assume you have the Beocentre 9500 service manual. I've just had a look at it and the test function for the CD appears to be slightly different to the CD3300.
On the CD3300 once in test mode we have;
Test mode 1 - tests the connection of the ribbon cable from the servo board to the radial arm. Pressing FFD >> or REV << swings the arm fully out (with some force) and then back again. There is no gradual movement. [I can't see this test in the 9500 book]
Test Mode 2 - does focus test [seems to be the same for the 9500]
Test Mode 3 - tests motor [seems to be the same for the 9500]
Test Mode 4 - tests radial search. In test mode 4 if you don't get the F4 error pressing the FFD >> or REV << gradually (by gradual I mean it will take several seconds of continual pressure on the >> to get to the end) moves the arm fully out and then back in again. [I assume this is your test mode 4, 5 and 6. For example, it says in the CD3300 book "press << and the Laser arm jumps backward across 64 tracks"]
With regard to help on the CDM4/24 have you seen this thread;
https://archivedforum2.beoworld.org/forums/t/35846.aspx?PageIndex=1
not sure if it'll help but it does go down the rabbit hole with regard to capacitor types on the servo board.
Tank you for your reply, this clarify quite a lot.
I do now believe the 5 ang 6 buttons entirely replaces your ">>" and "<<" buttons, as it seems to work the same way in mode 1. And since the unit can't find any track in mode 4 it jumps all the way there as well. The 9500 manual was not very clear on these functions. You have helped me to prove the arm can move quite at will in all modes (but it just don't seem to want to, and I cant see any claimed 650Hz signal).
Thank you for your information.
And yes I've studied that linked thread quite a bit. I have the recommended "blue" cap in the discussed C2103 position. It was the first ting I tried in this repair 🙂 I've also tried some other caps which is clamed to work, but switched back again. I've also tried the alternative adjustments of the "laser output" and "focus offset" to no help.
I'll try to get hold of an old analog oscilloscope for this weekend and look at the (in)famous CD eye test pattern on the HF signal, hopefully that gets me closer to a working unit 🙂
I feel I'm very close, but then again some oceans apart 😛
I do now believe the 5 ang 6 buttons entirely replaces your ">>" and "<<" buttons, as it seems to work the same way in mode 1. And since the unit can't find any track in mode 4 it jumps all the way there as well. The 9500 manual was not very clear on these functions. You have helped me to prove the arm can move quite at will in all modes (but it just don't seem to want to, and I cant see any claimed 650Hz signal).
Thank you for your information.
And yes I've studied that linked thread quite a bit. I have the recommended "blue" cap in the discussed C2103 position. It was the first ting I tried in this repair 🙂 I've also tried some other caps which is clamed to work, but switched back again. I've also tried the alternative adjustments of the "laser output" and "focus offset" to no help.
I'll try to get hold of an old analog oscilloscope for this weekend and look at the (in)famous CD eye test pattern on the HF signal, hopefully that gets me closer to a working unit 🙂
I feel I'm very close, but then again some oceans apart 😛
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Good luck. All this talk of oscilloscopes is now well above my pay grade 🙂
The other things I tried which you've not specifically mentioned you've done were;
change the voltage regulators
checked/changed capacitors in the power supply
resoldered most joints
and of course, swore at it on many occasions!!!
but I'm not sure if any of that applies to a 9500 system.
I'll be interested to see what you need to do to fix it.
The other things I tried which you've not specifically mentioned you've done were;
change the voltage regulators
checked/changed capacitors in the power supply
resoldered most joints
and of course, swore at it on many occasions!!!
but I'm not sure if any of that applies to a 9500 system.
I'll be interested to see what you need to do to fix it.
Well there was a tad of swearing just now...
I had 3 probe pairs connected, for HF, Laser output, and focus offset . Found the eye signal mentioned, at probably twice the signal strength necessary. Also a amped sawtooth noise signal at the strength of what the original signal should be was present when the "eye" was not there. Was supposed to try adjustments of one of the potmeters, when slipped, nocked over something on the table which pushed the cables and one probe jumped off its connection and slid over the PCB, probably shorting tings out. The signal was not the same anymore, laser output was suddenly doubled, disk span at highspeed and quite some other symthoms... Felt like I was almost there.. now two oceans away, at least... 😳
Well, now I have quite some more to troubleshot...
All your suggestions are qute on good and on the point, I'm afraid. I should have done all of them, but for some reason or other I've posponed them... Guess I was hoping to find the errors in al logic way, and maybe skip the work for some of it?
(I've checked the voltage levels, so regulators should be fairly ok. Well, might not be anymore...)
BTW: Oscilloscopes just looks confusing, but there are only 2-3 knobs to care about, the rest is just there to confuse you. One knob determines the height of the signal, in a Volt pr square format on the screen (up and down), and the other is the time pr square on the display sideways. The las button is to get the signal in the middle. not much more is needed, but they keep adding features you newer knew you ever needed. All one want is presenting the signal voltage amplitude for a certain time period 😛
I had 3 probe pairs connected, for HF, Laser output, and focus offset . Found the eye signal mentioned, at probably twice the signal strength necessary. Also a amped sawtooth noise signal at the strength of what the original signal should be was present when the "eye" was not there. Was supposed to try adjustments of one of the potmeters, when slipped, nocked over something on the table which pushed the cables and one probe jumped off its connection and slid over the PCB, probably shorting tings out. The signal was not the same anymore, laser output was suddenly doubled, disk span at highspeed and quite some other symthoms... Felt like I was almost there.. now two oceans away, at least... 😳
Well, now I have quite some more to troubleshot...
All your suggestions are qute on good and on the point, I'm afraid. I should have done all of them, but for some reason or other I've posponed them... Guess I was hoping to find the errors in al logic way, and maybe skip the work for some of it?
(I've checked the voltage levels, so regulators should be fairly ok. Well, might not be anymore...)
BTW: Oscilloscopes just looks confusing, but there are only 2-3 knobs to care about, the rest is just there to confuse you. One knob determines the height of the signal, in a Volt pr square format on the screen (up and down), and the other is the time pr square on the display sideways. The las button is to get the signal in the middle. not much more is needed, but they keep adding features you newer knew you ever needed. All one want is presenting the signal voltage amplitude for a certain time period 😛
@Insectdium I'm not sure if you told us the initial fault with your CD. Does it read discs at all and then not play? Or, does it not even read the table of contents?