Bang & Olufsen (B&O) Beomaster 2400-2 Problems

Archived from groups: rec.audio.tech,aus.hi-fi (More info?)

"Paul" <ozmodior@hotmail.com> wrote in message
news:bf1dafcc.0408080024.284f3da6@posting.google.com...
> Hi All,
>
> I recently purchased a Beomaster 2400-2. The guy I purchased it of
> assured me it was working fine, but when I got it home it was a
> different story....

**Hmmm. You could take it back.

>
> There seems to be a loud humming noise in the background, this seems
> to be present on all the inputs as well as the radio. I plugged in a
> set of headphones (thinking it might be the speaker outputs), but the
> hum was still there.

**I'd suspect power supply problems. In that old thing, you should be
considering replacing all the electros.

>
> The other problem is with the radio...FM5 seems to work fine (despite
> the hum) but all the other FM presets have no sound FM1 to FM4 (when I
> turn up the volume to the maximum, I can hear them faintly)
>
> I am just wondering if anyone has had any experience with these
> systems?, and could describe what the problem may be.

**Nope. That's a new on for me.

>
> I haven't had much technical experience, but I am adventurous with a
> screwdriver and soldering iron.

**Then I suspect you're headed for disaster. B&Os are notoriously difficult
to work on.

>
> If anyone has any schematics or any instructions on how to dismantle
> it, that would also be great.

**You'll have to call you local B&O agent and pay the Bucks for a manual.
When you quote the model number, make sure you also have the Type Number
handy. They usually want to know that as well.

>
> Given the problems, it is still a cool looking amp. I was gutted when
> I discovered that it didn't work as I had been after one for quite a
> while....

**Yep, B&Os are cool looking. As you will find, however, they are very
expensive to service.

>
> Any help appreciated,

**Buy a manual. Better still, get your money back.

--
Trevor Wilson
www.rageaudio.com.au

Archived from groups: rec.audio,rec.audio.tech,aus.hi-fi (More info?)

You'd better take it back, if he said there is nothing wrong with it!

Usually people sell things because there are problems with it. It is very
rare that these things come used with no faults. If a piece of equipment is
working well, there is no reason to sell it, unless it is from an estate
sale or bad dept problem.

To service it, you will need more than a soldering iron and a screwdriver!
You will need some test equipment, the service manual, and a fair amount of
service experience. The hum is most likely from some bad caps in the power
supply, and maybe some decoupler caps that have gone high in ESR. You will
need an ESR meter to properly test the capacitors.

As for the FM problem, fixing the hum may also fix this, or there may be
some front end problems. The front end of the receiver is fairly complex to
service, and someone going in that area without the knowledge of servicing
RF circuits will probably do more damage than good.

You would be best off getting an estimate from a B&O service rep, and if you
find it too expensive to service, then you will have to swallow your losses
if you cannot return the set to the vendor.

--

Jerry G.
==========================


"Paul" <ozmodior@hotmail.com> wrote in message
news:bf1dafcc.0408080024.284f3da6@posting.google.com...
Hi All,

I recently purchased a Beomaster 2400-2. The guy I purchased it of
assured me it was working fine, but when I got it home it was a
different story....

There seems to be a loud humming noise in the background, this seems
to be present on all the inputs as well as the radio. I plugged in a
set of headphones (thinking it might be the speaker outputs), but the
hum was still there.

The other problem is with the radio...FM5 seems to work fine (despite
the hum) but all the other FM presets have no sound FM1 to FM4 (when I
turn up the volume to the maximum, I can hear them faintly)

I am just wondering if anyone has had any experience with these
systems?, and could describe what the problem may be.

I haven't had much technical experience, but I am adventurous with a
screwdriver and soldering iron.

If anyone has any schematics or any instructions on how to dismantle
it, that would also be great.

Given the problems, it is still a cool looking amp. I was gutted when
I discovered that it didn't work as I had been after one for quite a
while....

Any help appreciated,

Cheers,
Paul

Sydney, Australia

Archived from groups: rec.audio.tech,aus.hi-fi (More info?)

>>Usually people sell things because there are problems with it.
>
>????? fairly one dimensional generalisation don't you think???
>
>so the entire second hand market is faulty?


Have to agree---it's a pretty silly generalisation. I've been Ebaying
now for some years with no problems. My experience is that people
don't sell faulty things directly; if they believe it's faulty they
take it to Cash Convertors so they don't have to cop the flack when
you come back complaining. But that's not to say Cash Convertors is
all faulty stuff either; just that you need to bear the above in mind.
In any case they give a 30 day guarantee.

>
>>It is very
>>rare that these things come used with no faults.

Mostly wrong. There are any number of reasons why people sell things,
of which faults is but one. People's requirements change. They just
crave something different. If they still like something and it goes
faulty, they get it fixed. Methinks this poster has had some very
unfortunate buying experiences indeed.


>
>most B and O second hand equipment is faulty
>or most second hand equipment is faulty??
>
>>If a piece of equipment is
>>working well, there is no reason to sell it, unless it is from an estate
>>sale or bad dept problem.

See above. More life experience or more imagination required here.

>
>Do youthink the trading post should type the above as a disclaimer??
>
>Doyou think such a sign should be displayed in cash converters??

The mere fact that the second hand market is burgeoning gives the lie
to all this. And long may it live as far as I'm concerned.

Archived from groups: rec.audio,rec.audio.tech,aus.hi-fi (More info?)

ozmodior@hotmail.com (Paul) wrote in message news:<bf1dafcc.0408090001.1c6a7583@posting.google.com>...
> Thanks for the info....looks like a job I probably won't be able to do myself...
>
> I wish I could take it back, but I purchased it from a flea market :-(
>
A B & O at a flea market? How dreadfully unfashionable by dear.

Ayn Marx P13 + DD12

Archived from groups: rec.audio,rec.audio.tech,aus.hi-fi (More info?)

The Beomaster 2400 can be serviced by a careful hobbyist, but if you're
a neophyte, it's going to be a challenge, because everything fits
together "just so".

That said, I'd get ahold of a service manual before proceeding. Stare at
the schamatics until they begin to make a bit of sense. One area I'd
look at would be a low-voltage supply used in switching audio sources:
The B&O injects a few volts of DC into the signal lines, causing signal
to flow (or not) through IN914 switching diodes. Kind of clever, but
that small power supply does fail from time to time, and when it does,
hum and/or unresponsive touch controls are the result.

I've also heard from other B&O restorers who claim that the original
electrolytic capacitors are failure prone and must be changed. There are
lot of electrolytics in the thing! I plan on eventually doing just
this to my own 2400, but after all the work, I don't think I'd ever be
able to break even in resale.

A pretty nice-sounding receiver overall; the FM tuner is best with
strong, clean signals.

Paul wrote
> Hi All,
>
> I recently purchased a Beomaster 2400-2. The guy I purchased it of
> assured me it was working fine, but when I got it home it was a
> different story....
>
> There seems to be a loud humming noise in the background, this seems
> to be present on all the inputs as well as the radio. I plugged in a
> set of headphones (thinking it might be the speaker outputs), but the
> hum was still there.
>
> The other problem is with the radio...FM5 seems to work fine (despite
> the hum) but all the other FM presets have no sound FM1 to FM4 (when I
> turn up the volume to the maximum, I can hear them faintly)
>
> I am just wondering if anyone has had any experience with these
> systems?, and could describe what the problem may be.
>
> I haven't had much technical experience, but I am adventurous with a
> screwdriver and soldering iron.
>
> If anyone has any schematics or any instructions on how to dismantle
> it, that would also be great.
>
> Given the problems, it is still a cool looking amp. I was gutted when
> I discovered that it didn't work as I had been after one for quite a
> while....
>
> Any help appreciated,
>
> Cheers,
> Paul
>
> Sydney, Australia