Beocord 8004 - Left channel missing

Hi all, 

I finally started work on my Beocord 8004 which had been sitting on a shelf for three years. It is a companion to the Beomaster 8000 I restored. I never even tried it before. There are however two problems. 

Left channel missing
There is no audio coming off the left channel. Using my tracer I can see that the head itself is outputting audio. It just dissapears on the main board, almost immediately. I have a service manual but am scratching my head at this currently as there is absolutely no context for the schemas. I am suspecting the little relay as this appears to be the first in the chain, but I am absolutely not sure. 

LED segments missing
It seems that I need to redo the LED boards. Luckily I know how to solder SMD components with a microscope. But I am wondering if anyone can share which LEDS they have used (make and type or perhaps an order number from Mouser)? 

Many thanks for your help! 

BB

 

The led problem seems to happen with nearly every display with those big digits. I renewed the leds in my Beocenter 7700. The new leds were much brighter, so I had to adapt the resistors for lower current. The original leds are crystals that are bonded directly to the pcb. has no longer contact to the board. You may be lucky to resolder them. But new leds size 0603 will fit.

Hmmm. It seems the problem is on PCB 2 (which hangs under the hood). But for the love of me I simply cannot get it out. 

Is there some magic sequence I need to do? There are no screws, it is just suspended via plastic hooks from the chassis. 

I stopped trying to get it out because it is easy to crack this board. 

Does anyone know what the correct method is? 

BB

Thanks, I thought as much. But those are 'naked leds' and resoldering them is likely a lot more work than actually installing new leds. Also best to just remove the board once and then do all the work, these connectors are prone to break with desoldering. 

I have 0603 leds so i'll try them for test on a becord 8000 that is broken beyond repair. If anything goes wrong no harm done :-). 

I don’t remember the pcb number, but you need to take off the glass. Simply slide the bar between the glass and the aluminum to the right. Then the glass is loose

notwist:

But those are 'naked leds' and resoldering them is likely a lot more work than actually installing new leds.

Oh sorry, that was not clear enough. I spoke of the wire, which you may try to resolder.

Got it :-). 

For PCB #2 you actually need to remove the front first. I could have guessed this but the Beocord 9000 service manual details it. 

Now to find context for the schematics :-)

BB