[filip_kbh]

I think it sounds more like a dirty lens. I do not know the Beocenter 9000 but if it contains a CDM 12.4 mechanism, I linked to a video on how to clean the lens from the underside, including the mirror in the thread called How To Fix The Laser In Beosound 9000.

[filip_kbh]

Finally got around to removing all of those capacitors.

Apparently C67 and C68 were never fitted from Bang&Olufsen, so I guess they must have suspected that they were not necessary.

I am listening to my BM7000 now, and I agree that it takes away a layer of ‘muffleness’ – it’s like removing a blanket in front of the speakers.

Thank you for suggesting this mod. I wonder why B&O fitted the board with those capacitors in the first place.

[filip_kbh]

It’s C2103. Indeed it’s the blue one to the left of the microprocessor on the above board. A very simple capacitor to change, as long as you get the right one 🙂

[filip_kbh]

I spoke too soon. It worked on my living room table.

And I have narrowed down the problem. I have an Almando surround box II connected to Powerlink. When that is plugged in, the datalink does not work. Argh.

[filip_kbh]

Just reporting back. Everything works now. Still there is the high-pitched noise that I presume may come from the display of the BL3500. The display does not show the clock – but I guess it would take it from a video source and not just the BM7000?

I inspected the pre-amp board of the BM7000 and could see multiple cracked solder joints, also for D5, so I presume that is where the fault was.

[filip_kbh]

Thanks a million. I really appreciate the help.

/Filip

[filip_kbh]

Great – I will order those parts and let you know how it goes.

There are several versions of the BC547 – an A, B, and C version. Which one to choose? Or will they all do?

[filip_kbh]

I have now tested for continuity between all pins. There is only continuity where there should be continuity. My money is on the BM7000. I saw Die Boegener made reply to someone around datalink not working after a thunderstorm. Since I did not have my BM7000 since the beginning, I have no clue what has happened to it previuosly.

At https://archivedforum.beoworld.org/forums/p/28464/223667.aspx he replies:

…

some parts in the datalink section are dead. Nothing special, 50 cents on the pre amplifier board.

Replace:

D5= 12V zener diode 0.5W

TR1=BC547

That’s all…

Not sure if I should look into that at some point.

[filip_kbh]

I checked for continity on all pins.

Reconnecting the cable, there is now stereo sound in the beginning until the 3500 randomly shuts off. I obviously don’t know if I connected the different ends differently this time around. Again, it refuses to turn on for more than 1 second.

[filip_kbh]

Yes, I also tried that. Pressing the mute button on the panel, I can listen to the CD that I am listening to on the BM7000 but there is only sound from the right channel. But I can’t turn it off by pressing mute again – there is no reaction. Now it turned off by itself, and I can’t turn it on again by pressing mute. Very strange.

[filip_kbh]

I have now re-done the option settings while everything was connected to mains. Pressing Radio turned on both the BM7000 and the BL3500 but the BL3500 shut off after a second.

Regarding the previous question, the datalink cable is connected to the socket called AUDIO OUT LINK on the 1611 box.

[filip_kbh]

I just tried. Disconnected everything. Turned on the BM7000 and set it in A.OPT1. Disconnected it from mains. Connected the BL3500 to mains and set it in L.OPT6. Disconnected it from mains. Then turned on BM7000, thereafter BL3500 and finally the 1611 box. It still does not work – argh, this is so frustrating.

[filip_kbh]

If the datalink cable is disconnected from the BM7000, I can turn on the BL3500 and change sources. I guess this points to a problem with my BM7000 then? The 7-pin datalink cable is brand new, so I don’t think that could be faulty.

I have no way of testing with a different ML cable, unfortunately.

[filip_kbh]

The beolink converter is type 1611, item 1161166, SW 1.3

[filip_kbh]

I tried option 6. It turns on for a second and then turns off. I wonder if there could be a fault on the BL3500. Also, there is a sort of high pitched sound in the left speaker of the BL3500 which I suppose should not be there. It’s there independent of whether any connections have been made.

Thanks for the help so far.

[filip_kbh]

Display shows “ML on”.

BL3500 SW version is 3.1

Serial no is 2058xxxx.

 

[filip_kbh]

The datalink cable has 7 pins, yes.

[filip_kbh]

First of all, it sounds like you have a muting relay problem (faint sound in the Beolab 8000, assuming that they are connected with Powerlink cables and that the setting is correctly chosen on the speakers). Do you have sound in the headphone socket if you connect a headphone?

Secondly, the Master Control Panel 5500 showing ‘No Contact’ is only a sign that there is a problem with 2-way communication. The error can either be in the MCP5500, the BM7000 or possibly both. If the Beolink 1000 does not send out signals, I would first suspect that the battery case is not making proper connection to the batteries – it’s a common file that is easy to fix.

Regarding the Beomaster 7000’s lack of IR response, I would first suspect surface-mounted caps (SMD) on the IR board. But you could start off by simply cleaning the sensors that are bound to be dirty from dust and cigarette smoke.

If you buy another BM7000 there is absolutely no guarantee that you will not run into similar problems or even new problems. they are 35-years old, and they need maintenance, like e.g. a car would not be expected to run for 35 years without exchanging oil, filters, battery etc.

Let us know how it goes.

[filip_kbh]

I think perhaps it would be great to specify which Beogram you have. If there is a threaded bar, I am thinking Beogram 4000/2/4. I have used a silicon lube for mine which seems to be working great since lubrication some years ago.

[filip_kbh]

Have you tested the fuse?

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