Fixing a beolab 4000 mains board

9 replies

Hello all, I have recently acquired a pair of beolab 4000 but one of them had the mains board destroyed. The solution of the previous owner was to bypass it by using some kind of relay. I have found an original mains board but it works with 120V. I am living in Greece and the mains here is 220V. I thought of buying it and substitute the 120V transformer with the 220V that my beolab 4000 has. Do you think it will work?

Any answer is welcome πŸ™‚

You are talking about the Standby transformer which is the same for for both 120v and 220v you just need to unplug the two small round fuses for 120 volts and put one back in a different position.

Basically the transformer has two primary winding's which are with one fuse in series and with two fuses in different positions which puts the winding's in parallel. 

Location: Hampshire, England

Hello Keith and thank you for the answer. I am talking about the mains switch board marked with the number one in the service manual.

If I buy a mains switch board that is made for the US market (hence working on 120V) and unplug the two small round fuses (F2 and F5 according to the diagram) and substitute the with those for 220V the mains board will work?

Keith Saunders wrote:

You are talking about the Standby transformer which is the same for for both 120v and 220v you just need to unplug the two small round fuses for 120 volts and put one back in a different position.

Basically the transformer has two primary winding's which are with one fuse in series and with two fuses in different positions which puts the winding's in parallel. 

Ok I think I got what you mean. The only thing I need is to take away the F4 and F3 fuses and install an F5 (according to diagram). The F5 should be a wickman type fuse 63mA. Is this correct?

Tassos wrote:
Ok I think I got what you mean. The only thing I need is to take away the F4 and F3 fuses and install an F5 (according to diagram). The F5 should be a wickman type fuse 63mA. Is this correct?

Correct, see diagram below

 

Location: Hampshire, England

Thank you Keith!!!😁

Hello again. The mains pcb arrived yesterday but at the end the problem was not the mains pcb. The relay was installed to send 5V so the speaker will turn on. I am afraid that the Amplifier PCB has some serious damage. Any ideas? Or any spares available????

If you won’t succeed in finding one, I have a service for refurbishing damaged boards for dealers, traders and customers.

Boards are ultrasonicaly cleaned and provided with a number of new parts and coated again. 

Just send a pm when interested. 

Location: Utrecht

Quite a challenge to achieve "Less is More" while having the Beovirus.

Hello, do you know if the standby transformer of the bl8000 is the same as the bl4000 and wherr can you find a substitute?

 

 

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