[Donby]

So – I’ve had done some wrestling with this Beosound 1, which have a faulty CD section. All good until the lens start to focus. I hear the click/tack sound, and then – nothing.

I have put a 1×1 cm piece of paper over the lens, and watched the scenery from the side, hoping for a some red light, – nothing. As I understand the lens must catch focus on the CD, before the CD start spinning?

I have read a lot of commentary, and obviously I replaced the laser. No joy – same result.

Some have mentioned bad capacitors, so I have scrutinized the printboard for bad looking capacitors. That’s where I want your opinion.

When I compare the 47uF/16V ones, like no. 2301, a couple have a slight curved top, while others are complete flat. I magine that it take some internal pressure to make it curve even a tiny bit, which is a bad sign.

Any experience and thoughts?

 

 

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Location: Denmark

[Donby]

An amazing comprehensive description of how to replace the laser section. Well done Guy

I found this one, as a friend of mine came with a Beosound 1 with a faulty CD player.

Why come to me? Well actually I participated in the development of the first compact disc player (CD50 – AIWA OEM inside)  from Bang & Olufsen in the early eighties.

Fun fact; The Compact Disc Player was introduced in May 1983 coordinated between Philips and Sony.

Meanwhile I left B&O 40 years ago.

Question regarding the Beosound;

As I have not dismantled the unit yet, – still missing a long narrow 20 torx.

I observe that it can load a CD, but the disc does not spin up. In which sequence does it continue? Does the laser light up to focus on the disc before/simultaniously with the disc rotation start up? No light – no detection of disc and consequently no spin up?

Or otherwise?

When I get access, will I be able to see a glimse of red light from the laser, if it works?

All this before I order a new unit.

 

 

Location: Denmark

[Donby]

Thank you very much Filip.

I was almost sure about that, but just  – ‘livrem og seler’😊

I might replace the trimpots after alignment. Out – find how many Ohms, and probably make two fixed resistors i parallel do the same. In a Beomaster 9000 I have seen a similar trimpotentiometer perform erratic after af few decades, resulting in a pretty hot output stage.

 

Location: Denmark

[Donby]

Hi Filip

I saw that you aligned idle current between 2TP200 – 2TP201  for 11 mV  , and similar for the other channel.

I suppose that is across both emitter resistors 0,22ohm?

Cannot find these TP stipulated on diagram or print.

 

Location: Denmark

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