The Workbench

Re: Workshop: Fixing broken LED Displays on BM6000/8000, BC7xxx

ablaumeise — Mon, 13 Apr 2009 20:22:45 GMT

Sorry, I didn't have a that close look at the other thread. You said 'my LED fix project', thats why I thought yours was the one at the beginning.

I also used size 0603 LEDs, though mine were 12,5mcd.

Your repair is really good work too....much more precise than mine.

Re: Workshop: Fixing broken LED Displays on BM6000/8000, BC7xxx

GDSammet — Mon, 13 Apr 2009 14:47:28 GMT

You're referring to the other contributor who replaced all of the resistors. I did not do that. My post was towards the end. I added headers to all of my displays to make them easier to remove. Take a look at the post. I have very nice pictures. Like you, my soldering was very precise and did not require cutting the display to fit around the LEDs.

I used 0603 size which is a standard (1.6mm x .8mm and 14MCD). The 14MCD is almost exactly the same as the original LEDs. Here are the parts I used:

I order all of my parts from Digi-Key in the US (DigiKey.com). They are fast shippers and have a great return policy. Here are the part numbers I used:
67-1548-1-ND (0603 SMD LED) ($0.125 USD each)
SAM1002-11-ND (11 position Low Profile Header) ($2.59 USD) These are connectors for the Volume display
SAM1109-11-ND (11 position Low Profile Receptacle) ($1.68 USD) These are connectors for the Volume display
SAM1112-12-ND (12 position Header) ($2.08 USD) These are connectors for the Balance display
SAM1122-12-ND (12 position Receptacle) ($1.51 USD) These are connectors for the Balance display

Re: Workshop: Fixing broken LED Displays on BM6000/8000, BC7xxx

ablaumeise — Thu, 09 Apr 2009 02:41:21 GMT

I have to admit I just bought the cheapest and smallest ones without having a closer look at the specifications. Luckily it worked.

But you can have a look at the Datasheet here (warning: download link).

Re: Workshop: Fixing broken LED Displays on BM6000/8000, BC7xxx

geearr — Wed, 08 Apr 2009 21:51:41 GMT

Another interesting contribution to this popular topic - Thanks very much for the time and effort.

In step 6 you referred to the "SMD LEDs" but apparently there is quite an extensive range. Can you provide further details of the exact model that you used, - voltage, mcd etc. That would help a great deal.

Thanks again

Geoff

Re: Workshop: Fixing broken LED Displays on BM6000/8000, BC7xxx

ablaumeise — Wed, 08 Apr 2009 17:46:29 GMT

Aww....I didn't see that one, otherwise I wouldn't have posted this guide.

Anyway, my solution differs from yours in some points: I didn't replace anything else than the LEDs...so no additional/new resistors or something like that.

Also, in my case the digits plastic thing fitted without modifications....might be because I used smaller LEDs or soldered more precisely.

And I didn't replace all LEDs...just the ones that I couldn't bring back to life. Seems I chose the right replacement LEDs - you can barely see the difference between 'old' and 'new' when the display is switched on.

Re: Workshop: Fixing broken LED Displays on BM6000/8000, BC7xxx

GDSammet — Wed, 08 Apr 2009 14:08:27 GMT

I had just posted my LED fix project too. Good work.

http://forum.beoworld.org/forums/t/24203.aspx

Workshop: Fixing broken LED Displays on BM6000/8000, BC7xxx

ablaumeise — Mon, 06 Apr 2009 15:46:48 GMT

I was just repairing a BM6000 display and remembered someone asking for a guide on repairing the LED-Displays in the Beosystem 6000/8000 components some time ago.

And so here it is (should be very similiar - if not identical - to the displays used in the Beocenter 7000 series):

First step:

Desolder the display from the circuit board (self-explanatory, isn't it? So no pictures here). Before you do so, make a sketch to remember which digits are not working.

Step 2:

Remove the white and red plastic parts on the back of the display using a knife or something similar.

Step 3:

Now you should be able to remove the red plastic cover and the newly revealed white plastics. What is left now is the bare circuit board.

Step 4:

Now you can see why these displays fail that often. The thing in the middle of the black spot is the LED itself. And then (barely visible) there is this thin wire running to the contact left of it. This wire is not soldered, it is just pressed (maybe also glued?) on the board. So with time it just loosens and thats when the digit stops working.

Step 5:

So all in all it should be a simple fix - sadly it isn't. Theoretically it should be enough just to add one tip of solder to every of the wire contacts. The difficult part: Don't leave the solder iron there for too long! About one second should be enough - otherwise you can damage the LED. In my case this worked for most of the missing digits - sadly not for all. Two of them were completely missing the wire - no idea if it was my fault or if it already was like this...

If there were no missing wires on yours - reassemble it and test. If some digits are still not working: Remove the plastics (but leave the display soldered on) and try to solder with the display switched on. You can immediately see if it worked and sort out the usual bad contact problems.

The following steps are optional and only required if you couldn't fix all the digits with the steps described above.

Step 6:

Order some red SMD-LEDs. You can get them very cheap in online shops. I ordered mine here.

Step 7:

Scrape off the old LED (the black spot).

Step 8:

When you unpack the new LEDs (beware - they are really, really small) you will see a marking on the back - usually a small triangle. The vertex of the triangle must point to where the black spot was. Well, and now you just have to solder them on. Pretty easy, isn't it?

I hope this will someday help someone repairing this BM/BC.