My beloved 1900 was rockin' when it gave a loud 'crackle' that was followed by a strong electrical smell. The back of the unit (fins) was very hot. I unplugged it and let it cool. The fuse appears to be OK.

When I tried it later all I get is a 'bzzzt' when each button is touched (Eg. Phono, FM1, FM2, etc.) and the lights only flicker when a button is touched. In the past I have experienced one channel cutting out but slightly moving the Balance slider has restored the channel. The Balance light has been out for a number of years.

Does anyone know if the unit can be repaired or if it is worth repairing. I'm not able to do it myself so I would be grateful if you can recommend a repair shop in the Toronto, Canada area. This is my first post on the Forum and I am very thankful for any help you can provide. Thanks.

Beomaster 1900 (#2904), Beogram 1900, Beovox S60.

Welcome to Beoworld ! 

Your Beomaster probably sufferred from oxidated idle current trimmers.
That's very common and it puts the idle current of the output stage(s) to maximum.
This will most likely have burned one or more of the emitter resistors, causing the electric smell (and eventual smoke).
The output stage transistors and their solder joints should also be checked. Needless to say, the trimmers also need
replacing and readjusting.
Sounds drastic but shouldn't be a very costly repair.
Finding a good repairshop in Canada seems to be hard. I get repairs in from Canada occasionally and I'm in Denmark...

Worth having it fixed in my opinion, especially since you have a fine Beosystem there.
I like the combination of S60's speakers with the BM1900.

Martin

In the early 1980's, I was the (young) Sales manager for Grundig in Canada.

Remember the Satellit 3400, and 650 radios (When Grundig was a real company, not a Chinese knock-off name)?

Some of the stores we sold to, were also B&O dealers, and I got to know their service personnel quite well.

In Canada, there are 3 B&O techs (with lots of grey hair) who could look after your unit in the way it deserves.

2 are retired.

In Toronto, there is All in One Electronics in the Dufferin / Eglinton area  - 416-789-0668.

I have known Robert Tracy for nearly 30 years, and he knows vintage B&O like no other.

In a visit to Toronto in 2007, I also met his fellow techs from Denmark and Germany there, all with eons of B&O experience.

We swapped war stories about our favorite restorations - had a great time.

Tell him you want all the electrolytic capacitors replaced as well - he is quite OK with full restorations, as opposed to limited repairs.

I assume that he's still in business, if not, contact me off-line.

Menahem

BM 1900 Restored

Many thanks to Dillen and Menahem for their advice.

Robert Tracey of All In One Electronics in Toronto (Canada) worked his magic and I'm back in the music business.

jbh:

Many thanks to Dillen and Menahem for their advice.

Amen!

Glad to hear it got sorted!

Welcome to the forum, and stick around!

Glad it worked out for you!

Would you like to let us in on the secret of what exactly was done technically?

Menahem

So glad you have got it sorted

Andy T.

Menahem

Here is what the work order stated:

Replaced parts listed/Repaired power output stage/Adjusted bias/Cleaned/Tested all functions.

Parts:

2 Transistors TIP141 & 2 Transistors TIP146

2 Resistors .33/3W

1 Diode IN4148

2 1K Bias Potentiometer

As well as fixing the 'short' all the lights are now working and the intermitent problem with the right channel cutting out has been fixed.

Yup, those are definitely all output-stage components.

He's right on the money!

What about all the electrolytics, or have those already been replaced recently?

Great !
And quite as expected then.
The 1K trimmers are a bit odd though since the originals are 220 or 250 ohms.
1K trimmers will work fine but would have been quite tough, though probably not
impossible, to set just right.

Also nice to have a reference to a good repair service in Canada.

Martin

Hi Martin,

You're right on that the trimmers are about 250ohms, but today, I cannot find those intermediate value trimmers anywhere.

The 2 most widely available manufacturers of trimmers - Bourns and Piher, make available at the big distributors only 100ohm, 500ohm, 1K, 5K, 10K, 50K, etc.

I would have used a 500ohm trimmer in this case.

Do you have a source for the intermediate values?

Menahem

I find them generally available and always have most of the values in stock.
Reichelt in Germany can supply both 220 and 250 ohms, both Piher I believe and both will work fine in the BM1900.

Martin