The Bang & Olufsen Beomaster 2400 is now fully functioning.

Volume indicator lights did not work due to a broken transistor in the control circuit. (BC549C)

Besides the fun of troubleshooting, with every repair you learn something new! 🙂

Now on to the next project on the list… 🙂

This is just a short update.

The “Stand by” is now working.
It turned out to be easy.

A 10 MOhm resistor needed to be changed, and a couple of resistors that were to fond of each other and hugged a bit, making a short…
When they were separated a little bit, it started working. 🙂

I have worked on some of my other projects for a while now. 🙂
(Reel to reels : Revox A77 2 track high speed, Sony TC-366, Sony TC-377.)
Hm, maybe i´ll make a post about them too…
I always take a lot of pictures, so maybe.. 🙂

The Beomaster though are closer to be fully functioning now. 🙂

After changing the capacitors and lamps, it blew a fuse at first power on…
Turned out to be a broken power transistor.
After ordering and receiving the new power transistors, and mounting them, it started up.

But only one channel was working…
After checking around the power transistors, i could rule them out.
I started to follow the audio-signal, or the lack of an audio signal, backwards in the circuitry.
I got all the way to the balance potentiometer. 🙂
Turned out that the small contacts that moves along the tracks were loose due to small broken plastics that should keep them in place.
(That, and the tracks were dirty… 🙂 )

This is apparently a common problem with these.
But luckily, Martin a.k.a. Dillen at Beoworld had a kit with newly produced plastics. 🙂
After disassembly and cleaning of the balance-control, and replacement of the plastics that were broken, both channels are now working.

The same contact problem were to be found with the bass and treble controls, so they got the same overhaul.

So, it now seems to work. 🙂
Tuning in a radio-station and work the bass/treble controls, raising/lowering the volume works perfect.
Two things don’t work yet though…

#1, I can’t get it to power off using the “Stand by” control…
Nothing happens.

#2, The lights for the volume doesn´t change at all when changing the volume.

To be continued… 🙂

Main board now recapped, except for the two larger ones.

They are supposed to arrive today. 🙂