Peter wrote:

Staggering! Wonderful job and beautifully presented. I am deeply impressed.

Thanks

Hi,

I also have a couple of BL7000's that have fairly weak back lights. After reading this thread I decided to have a go at replacing the backlight as well as full recap and battery replacement on both BL7000's. I ordered a couple of backlights from Conrad and caps from Mouser. Followed the instructions in this thread and have successfully completed the replacement. Only tricky part was aligning the display contact pads with the contact pads on the PCB.

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Top is the cold source backlight from Conrad. Lower is the Original B&O Backlight. Interestingly the backlight voltage on my Beolink measured about 95 volts. Yet to measure what it is on the other BL.

Picture below shows the display board and keyboard flipped up exposing the lower CPU board. Even though two way communication worked on this remote I decided to replace all the capacitors since I had the remote apart. Just as well as the IR area around the top of the display board had the tell tale fishy smell of the leaking SMD caps. My ESR meter will read up to 20 Ohms but it would not give a reading on the SMD caps! Amazing the comms still worked.

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Lower CPU board removed and shows the Sanyo CR2430 battery. This measured around 3 volts but I decided to replace it with a new one considering it is 20 plus years old.

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Beolink on left with new backlight. Difficult to photograph, but it is very bright and clear. Display looks washed out in photo but it is just the camera having difficulty with the two brightness contrasts. Photo does not do it justice. Beolink on right is next up for same treatment.

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MartinM wrote:

I also have a couple of BL7000's that have fairly weak back lights. After reading this thread I decided to have a go at replacing the backlight as well as full recap and battery replacement on both BL7000's.

Very nice to see. 🙂

As you mentioned, aligning the contact pads are the delicate thing in this operation.

Great job  MartinM, now I definetely will give it a try myself. Ordered the components at Conrad.

I have seven of those that needs new backlights so let's start with one first!

@Leslie,

I like your new profile picture. 😁

Some don't but hey, it's Christmas and nothing happened today (yet)!

Disassembled my next BL7000. Here is the reason why I remove the CPU board and replace the battery.

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I've desoldered one leg and bent the battery back on the other leg exposing the underside of the battery. As can be seen, the battery has started to leak.

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Close up view of the leaking battery. Last thing you want is acid on the very small traces on the pcb. Even if the battery looks ok, I still replace it given its age.

That's a great shot! Never knew that this could happen! Will check mine(s) if it has the same issue.

Waiting for Conrad parts🙂

What type of battery is this and how can you replace a new one since this has been soldered. Is it save to do soldering on a new battery?

The battery is a Sanyo Lithium CR2430 (24.5mm diameter by 3mm thick). I bought some replacement batteries locally that have the solder tabs. I definitely wouldn't recommend soldering directly onto this type of battery.

Take lots of care when desoldering the battery and use an ESD safe area if you can.

I'm in the process of cap, battery and backlight replacement of my other BL7000. I've taken some photos here that I missed with the other one regarding the display alignment.

Display flipped up and backlight removed, ready for replacement. You can see the contact pads on the display and the black contact pads on the pcb.

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Once the new backlight has been cut to size and fitted, fold down the display and ensure the contacts line up as per next photo.

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You can see the contacts on the display edge that must line up with the contacts just visible below.