Thanx all of you believing in the project Martin has mentioned a very good point here when working on the power amps of bm8000. It is very easy to forget the tabs on the driver transistors. They need to be bent to make sure that the dont make a short to ground. Its also the same for the 3 large caps on the amplifier boards, they cant be higher than

Hi Laurence Thanx :) I have drawn the PCBs by myself in the computer with the help of the old ones and the schematics in the service manual. Then I had them produced for me at a professional PCB manufacturer. I have done the 2 power amps and the displayboard. I will probably make a new CPU board too after finishing my bm8000 as a future spare since

Interesting thoughts about resistors... I know there are two schools in that issue, some prefer the old carbon types and some prefer the metal film. I personally prefer metal film resistors because they have higher stability, low capacitance (<0,2pF), lower noise than carbon composite, small size and they will not get into fire the way carbon composite

Thanx Martin :D I just felt the need of saving it from the electronics recycling, hoping that I can get it up and running again... /Fredrik

After testing the power amps on the workbench it was finally time to fit them in the chassis. A little tricky and time consuming work. Most tricky part is to route the cables right so theyre not get damaged in the small amout of place inside the beomaster. The pic shows the power amplifiers mounted in the chassis. This is where I am at the moment. More

The power amplifier PCBs and the display panel had been "over repaired" and got lots of burn marks from hot components. Some tracks of the power amp PCB were loose or broken, overall in bad shape. The display panel was cracked. I didnt want to keep it that way so new PCBs were made to replace the old broken ones. Top left pic shows original

Further examination showed a rusty bottom plate, so I decided to strip everything down to be able to clean and repaint. The top left pic shows the cleaned plastic part of chassis. The 2 pics on the top right shows repainted and refitted bottom plate and rear mounting frame. After that it was time for reassembling the powertransformers and the bottom

Hi all! Just a little story to share with you... Ive recently bought a bm8000 in "need for repair" state. However when I recieved it everything was loose inside, a good sign of a technichian who gave up repairing it, but the exterior was in good shape. At this state I didnt dare to power it up since some repair attempts were done on the output

Hi Martin I agree with you, the beovox from that era have an amazing sound. Im a proud owner of beovox M70 to my beomaster 8000 sytem and I am still surpriced of the sound quality, power, clarity and dynamics they reproduce although they are 30 years old. Poweramplifier constructions use many different output configurations, here are some: In the beosystem

Hi Ville The crossover have in total 5 caps, 2 electrolytic caps, 10uF resp 15uF. 2 polyester types 3.3uF, 1 polyester 330nF. All components in the 3000 are mounted on a small pcb so its very easy to replace. Use some silicon glue to fix the caps to the pcb to avoid vibration noises. Also make sure to get the speaker cabinet airtight again when reassembling