Hi dear Members

Seems that there is no soloultion for that Problem?...very sad.

Have a nice Sunday

Best Regards

Christian

Hi Fredrik,

I would be interested in the output amplifier boards.

If you are ambitious to take on the task a new pcb for the microcomputer board would really be welcomed :-).

-sonavor

Hi I would be very interested on the 5 and 8 PCB modules! 

Regards Egon.

Hi Fredrik. 

I am interested in pcb module 5 and 8.

Kind regards 

Henrik 

Hi

I have noted your interest!

I will list the prices of the PCB:s here soon when I got an indication of how many boards there are demanded in total as it affects the price/each. 

 

Regarding the CPU module I have no PCB drawing completed yet. I started to make that layout back in 2010 for my restoration project of the BM-8000 at that time. However my CPU board was in good order and still works fine so I never finished that drawing. I might continue that work in the future to help you save your BM:s but it is a very time consuming job since it is dual layer PCB. It would help me a lot if someone had a scrap module 9 for me I could take apart to reverse engineer it and make the drawing complete.

/Fredrik

Hi Fredrik,

Yes, the CPU module would be the most difficult. I will check my spares but I think all of my spares are working boards. Plus a decision will need to be made as to which of the two Beomaster 8000 Microcomputer board layouts to reproduce. I would vote for the later model as it has the easy to open shielding box. The earlier BM8000 units have a box that is soldered shut and a little bit of a pain to open. Do you already have some ideas on a replacement shield box? 

Also, Martin (Dillen) might have a non-working, faulty BM8000 Microcomputer board in his archive. 

-John

Hi John

Hmm I have not seen the older version of the CPU unit. Do you know if it differs much between versions except for the shielding box? Would be interesting if you have pics of both the versions to show me.

 

/Fredrik

Hi Fredrik,

I emailed you a few photos of the two Beomaster 8000 Microcomputer boards.
I will also post one of each here.

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You can see that on the early Microcomputer PCB the shield box completely removes. However, you can also see that the mounting points have places where the solder pads for the box mounts tore away from the board.

On the later serial numbers the top and bottom lids removed easily from the board but there is a frame for the box that is soldered to the pcb in a way that makes removing it a difficult chore.

The later serial number boards with the improved shield box resulted in components moving around a bit on the board and rerouting of some traces. Overall I think the later model boards are better but both work well when restored. 

I think a replacement board would be best to be modeled after the later board but with possibly a new (third) shield box design that mounts easier.

Troublesome issues with both legacy Microcomputer pcbs are the grounding plane and thin traces. It is common to find boards with solder pads coming loose along with part of the traces. B&O also released some service bulletins that called for running wires to and from points where the connections were a problem. 

I think a fresh new pcb would solve a lot of nuisance problems that show up in these aged boards. New board connectors will also help.

-John

Hi Fredrik,

I think you got yourself a market here!

Especially with John and Rudy 😕

I remember your work quite well and back then I was impressed.

Do keep us informed please!

How come you only have 5 posts by the way?

Did you have to re-join?

Best wishes,