Correct lamps here:

link

Don't expect it to work correctly with "12V" lamps. There are more to these lamps than their voltage rating.

Check also the balance potentiometer. It's known to break causing silent channel(s).
Repair kit here:

to confirm it might be the lamps, if I removed the lamps I installed and just leave them out, should it work (without a lamp) - I would think so being the old lamps were burnt out and had the same effect as being out, and I assume these units still worked (had sound) with dead bulbs).

Can someone also provide some more details on the type of bulbs needed???  First, are the 12V or 14V or even 15V?  Next you say there is more to them than their voltage - so what else is required.  I assume it must be the amp rating, and if so what is the proper amp rating?

Thanks

DanADaMan wrote:

to confirm it might be the lamps, if I removed the lamps I installed and just leave them out, should it work (without a lamp) - I would think so being the old lamps were burnt out and had the same effect as being out, and I assume these units still worked (had sound) with dead bulbs).

Can someone also provide some more details on the type of bulbs needed???  First, are the 12V or 14V or even 15V?  Next you say there is more to them than their voltage - so what else is required.  I assume it must be the amp rating, and if so what is the proper amp rating?

 

Thanks

You compare burned out lamps to potentially wrong new lamps and conclude that the new lamps must be right because with them fitted it still doesn't work? 😂

The current rating is essential, because the lamps form integrated parts of the electronic circuits, and they also direct an amount of current when not lit, which also makes their cold resistance interesting.

I don't recall the exact specs, but think about numbers like 16,4V 92mA or something strange like that, - they are not ones you are likely to find in shops etc.
Outline can be T1 1/2 or perhaps even T1 3/4.
I have even seen T5 socket types fitted, though they are often difficult to solder, because their pins are short and coated in stainless or something similar for use in sockets.

The ones I linked to above are custom produced for this specific use (- for a reason).
They are a little larger than T1 1/2 to make them fit their holders and they have
long leads that solders easily.

If you insist on using 12V or 14V lamps of unknown (to me and perhaps also to you) wattage - or a mix - and you are sure that those lamps are adequate for the Beomaster, you will have to diagnose a bit and find out why it acts up the way it does.
Put a scope to the signal path and see where it gets lost.

Did you check the balance potentiometer?
I have made repair kits for those too.

Did you check the lamp inside the LDR casing?
I have made that one too recently.

Martin
Repairing Beomaster 1900s and 2400s since 1977. 

so I was able to source some 12V 80ma bulbs and replaced the 9 bulbs that I previous installed with these newer ones.  Put it back together and it is now much better and actually can be heard quite well but at full blast is what I would compare to a quarter of the total output of a newer receiver.  I would have thought this unit would be more powerful?   

So my question - I know if the wrong bulbs are used that the unit can go into mute mode.  But mine is definately not muted but just not as loud as I want.  If again wrong bulbs are installed, can it cause the unit to not be in mute but also rob some of the available volume?   Just wanting to decide if I should try once more with a different bulb, or just leave as-is.   Unfortunately at the volume this is putting out I will likely not use it much and rather just have it as a display.  But then I bought this as a non working unit and never had one before, so perhaps these units just are not that loud?

The BM2400 is a 25W per channel amplifier into 8 ohm speaker loads. What are you measuring as the output you are getting?  If you had the Beomaster at full power into a fixed 8 ohm load (keep in mind that an actual speaker doesn't appear as a constant 8 ohm load) then you would measure around 14 Vrms across the speaker load. Around 6Vrms for 5 Watts.  Just under 3Vrms for 1 Watt.  How loud that is for a given speaker depends on the speaker.  What speakers are you using?

Back to the Beomaster amplifier though...did you restore it (new electrolytic capacitors, performed the service manual adjustments)?  What is the no-load (idle current) set to?  You may not have the output amplifiers biased for their recommended level. Did you go through and check the power supply voltages per the service manual?

-sonavor

I just found a way to breath life into the old 2400 beomaster even though it isn't the loudest.  I have a B&O tape, B&O cd and B&O phono - before I was feeding each of the player to my big Sony amp and really only used the beomaster receiver for radio and nostalgia - though as I mentioned it was a little low volume for my taste even after replacing the bulbs with what I think are the right ones.  Don't get me wrong - it isn't quiet now but just can't shake the walls.

So I now hooked the B&O tape, cd, and phono to the 2400 (I have an adapter that allows me to connect both the tape and cd to the tape input and switch between them with a button), and then feed the Sony big amp through the headphone out port of the beomaster - I also connected two stand alone speakers to the 2nd room connections.   So now if I want to just listen to the B&O by itself it works great and is decent loud on the 2 speakers I have it to (which are just small Wharfedale bookshelf speakers).  This is nice cause I can listen to radio, tape, cd, or phono.  But then if I want to shake the walls I turn on my Sony amp (which is connected to 7.1 speakers) and turn my Sony amp to the B&O input and boom.  The B&O feeds whatever I play to my big amp and speakers - sounds awesome listening to the old material (tapes, phono) through the B&O being feed to the modern loud amp with multiple sound effects.