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
Hi,
I have a Beomaster 1900 (Beomaster 1900-2 T2903), a friend gave me it with a pair of Beovox 2400. I would like to use it daily but there was a annoying "hum" at good volume. So I decided to change all the capacitors.
I bought the kit from beoparts-shop.com with all the caps needed.
Great, after a long time awaiting them, I finally found time to change all the 62 caps I found !
I made a quick test without all the panels and screws -> every tactile buttons worked (the phono was not working before, now it is), but no sound. I plugged an headset and then, I could only hear the radio when I pushed the volume to maximum. I though it could be a mass wire problem, so I put all the panels and screws.
Now I have a new problem: instantly after selecting a source, it goes to standby...
I check every caps polarity, sounds good, checked some wires, no one seems unsoldered.
More info: A service have already been made one time before I acquired it, all the 2.2uf have already been changed, but I replaced them. Also there is a strange part with long wires not in place (I guess it have been added by the person who serviced it long time ago). And I did not replaced the reservoir capacitor, not in the kit.
https://photos.app.goo.gl/s4bJZUPTtPaPRRSZ8
https://photos.app.goo.gl/jfNeEw4ZyrmM6zXy9
Could please help me find some things to test ? I only have a multimeter, no capacitor tester
Thx :)
Check the solder joints at the output stage darlington transistors.If they hang like in the photos, with heavy cooling fins, while you flipped over the board countless times, their solder joints will have broken.
In most cases, you can do a full recap to a Beomaster 1900/2400 without taking out the board.Just losen corners or sides enough to work in there as you go.
Martin
Ha, thought they were maintained firmly by screws. So I screwed up
Thx for the advise, I'll check that asap.
Full recap without taking the board out, damn if I knew that ! I tried to do as the picture shown in the kit. My bad
< this is a bug >
< this one too, sorry >
I just checked, seems ok for me:
Here is the link of the full album, I made photos of the soldering joints
https://photos.app.goo.gl/unwKkNJyh7KoAVZcA
I remove the front and back panels, and tested, I can select the source again, but still have problem with the sound really really really low.
Thx
Maybe the 2 red Roederer caps in the volume section of the control board has something to do with this ? They should go as well. Don't buy big ones, then you won't be able to close the lid
Beogram TX, Beovox S45, Beovox MC 120.2, BeoSound 1, CX50, Beovox S75, Beomaster 2400, Beomaster 5000, Beogram 5005
The shutdown is usually caused by DC present on an output. Cracked solder joints, shorted components etc.
Hi jesperb,
I don't really understand what are the Roederer caps sorry, could you highlight them on a picture please?
I should mention that the device was working "fine" before the recap 😅
Alright! I have great news: I'm stupid.
Haha, no but I forgot to plug a wire from the mother board to the control board (the one with three pins between Bass and Treble potentiometers).
Now the sound is higher (only tester on headset) but the sound is saturated all the time.
And the phono was not working again because the connecting pin was unsolderer. Resoldered it and it works again 👌
So: maybe there is a short-circuit somewhere 🤔
Nevermind, since you got it working - I just meant the old red caps on the sound control board. And i think they are in Martins kit, so maybe I have been looking at a before pic in your shared album
Well done, chapeau!
Ha yeah the picture was not up to date 😉
Thank you jesperb! And all the others from beoworld 👌
I appreciate to have support and advices, the beomaster is a real mess haha
I'm glad to tell: I made it! It's now working and the sound super clean compared to before (the saturated bass problem is only at high volume, and with headset). I'm super happy to make it work as new again. The sound quality is not incredible, but good enough (the capacitors from the kit are not audio grade, as the one this repair shop used https://beolover.blogspot.com/2017/11/beomaster-1900-type-2903-recapping.html?m=1).
I tried, I really tried to find the needed capacitors from the datasheet, but even with an exhaustive list, finding the new one looking the same as the picture was almost impossible and expensive.
Ps: should I consider replacing the two big "reservoir capacitor"? Or until it's work it's fine?
And should I consider replacing the 2-3 4,7uf in small green shape? They were not present in the kit, and I might able to read "loudness" around them in the pcb. Maybe they are dead and produce saturation in high volume?
I have to find a replacing light bulb, one died during the repair..
Anyway, Thx everyone :)