ARCHIVED FORUM -- March 2012 to February 2022READ ONLY FORUM
This is the second Archived Forum which was active between 1st March 2012 and 23rd February 2022
I'm currently trying to understands whats going on in my Beomaster 2400 and I would like to know if it's kind of failure is common and what exactly might trigger it: When put it under tension, after about five seconds, it goes back to standby. If I try to change a channel right from that point, it relay clicks to standby immediatly. If I wait, say, 5 minutes, it will stay on for about 5 seconds and goes back to standby immediatly. I then checked if, during this 5 seconds, I do have an output. When I connect a loudspeaker on the left, either the 1st or the second channel, everything's ok, I can ear the radio (for 5 seconds...) If I connect the loudspeaker to the right output, either the 1st or the second channel, I ear a kind of buzz, and then some strange stuff happens: it goes on and off, infinitly relay-clicking...I have to put it off manually or disconnect the loudspeaker to make it stops....I checked the solder joints at the base of the resistors in IC300 and 301, everything seems fine, no fuse seems to be blown. (At least the one that i'm aware of (near the big transformer and near the bridge rectifier...) Does anybody as been confronted with the same problem? Can it be caused by only one thing or a multitude of things? Caps sure need to be replaced but can the caps be the only problem?Thank's to all!!
Guillaume
Capacitors, idle current trimmers, the board mounted rectifier and cracked solder joints at the output stage transistors.With these things fixed, you can start diagnosing eventual remaining faults. Not before.
Martin
Exactly as Martin says, my 2400 had the same symptoms, when done with caps, trimmers and rectifiers, I found a couple of transitors in bad shape
If you change this, change the lamps also.
Collecting Vintage B&O is not a hobby, its a lifestyle.
Thanks to both of you... Since i'm not at all experienced (my only experience being solder joints repair of a cdx), I think I'll put that project on standby. I thought at first that someone could do the job here in Quebec but unfortunately the only person I found out experienced with B&O stopped doing them 3 years ago... So the beomaster will be only a nice decoration until then...
Thanks!
.....
After changing 51 caps, about 15 lamps (don't remember exactly...) and a bridge rectifier, my beomaster 2400 is now running perfectly. (1st big B&O project ever: 13 hours of work non stop) I never saw one of these unit working before, that small amp does sound amazing!!! I haven't change the big c92 cap though... In fact (that will sound stupid, sorry i'm unexperimented) but, do you need to remove the blue plastic thing around it before using it or it has to stay there?
Thanks to all, especially Dillen for his kit and instructions!!
This is SO satisfying...
Good job !C92 comes ready to mount.The blue wrapping is insulation. Keep it on.