Sign in   |  Join   |  Help

Beomaster 1900 + Constant hum + Hot

rated by 0 users
Not Answered This post has 0 verified answers | 5 Replies | 2 Followers

markvanloock
Not Ranked
2 Posts
OFFLINE
Bronze Member
markvanloock posted on Sat, Jun 22 2013 3:12 PM

Hello,

What a great forum. I've been reading in the hope of gaining courage to tackle my problem.

I have my fathers original Beomaster 1900 amp. Having admired it's beauty since my age could be counted on two hands, I'm very proud to now own such a timeless classic. Unfortunately it can only be admired when it is turned off, since the noise that's emitted when it is turned on is ear shattering.

The unit didn't used to be like this. When I first rescued it about 10 years ago it was fine, but it started to develop this loud hum in one of the channels after about being on for an hour. Gradually this period reduced until it was unusable, and so I parked it in my loft for the last 8 years or so.

When I first got it, a B&O repair centre sent me replacement bulbs which I recall were extremely easy to fit, but this problem will presumably require far more extensive surgery.

From what I've read, I assume I should start with a refurb kit that Martin can still hopefully provide? I think I should be able to cope with replacing the capacitors, but the talk of oscilloscopes and other fine measurements in the service manual worries me. I don't have access to that sort of equipment. Does this problem sound like too big an issue for an amateur , or is this a fairly common problem that's an easy fix?

The unit has always powered on and switched channels without an issue. I don't want my incompetence to make it any worse!

Many thanks,

Mark

All Replies

Søren Mexico
Top 10 Contributor
Mexico City
6,290 Posts
OFFLINE
Gold Member

Get the kit from Martin and get at least the idle current trimmers and the rectifier(s), check that the end stage TRs are OK, clean all the sliders and do an overall cleaning, you will need a multimeter to do this,

Collecting Vintage B&O is not a hobby, its a lifestyle.

Søren Mexico
Top 10 Contributor
Mexico City
6,290 Posts
OFFLINE
Gold Member

Forgot, welcome to the forum, and keep us informed

Collecting Vintage B&O is not a hobby, its a lifestyle.

Beobuddy
Top 25 Contributor
Utrecht, The Netherlands
3,520 Posts
OFFLINE
Founder

And, be gentle with the soldering as the traces are easy overheated and cracked by a to hot soldering iron.

Martin can provide, but the caps are common and to buy in every electronic-store...

markvanloock
Not Ranked
2 Posts
OFFLINE
Bronze Member

Thanks for the very quick responses!

It's not sounding any easier. It'll just be more rewarding when I get it working. :)

I'm going to study the diagrams I've found so all this makes a bit more sense. Its great there is still so much info around about this system.

Thanks,

Mark

Søren Mexico
Top 10 Contributor
Mexico City
6,290 Posts
OFFLINE
Gold Member

Go looking in the archived forum for Beomaster 1900 and 2400, lots of threads

Collecting Vintage B&O is not a hobby, its a lifestyle.

Page 1 of 1 (6 items) | RSS
Beoworld Security Certificate

SSL