www.mfbfreaks.nl

[analogadikt]

Greetings from India.

I am a music lover and enjoy listening to music from all over the world. I prefer analog formats, mainly LP records and vintage equipment. Last week I found a pair of Philips 541 MFB speakers and purchased them.
Unfortunately one of them is not working and require help and guidence to repair this.

The power indicator light on the speaker that is not working is blue color while the speaker that is working is amber color. Does this indicate anything?

Also, what is the function of the output terminal? Does it allow another external speaker to be connected to the internal amp in these speakers?



With Best Regards,

analogadikt

[mattie]

hi

from orgine the lights on the front are red , stay they on even after half an hour no music in the inputs ? if so , in meny cases is the 330uf elco whitch regulates the automatic switch defect this is a axial elco .

replacement of all elco's exept the bigones on the metal plate is recommended they are 35 years old and your country is very warm .

replacement of the elco's is when you do it yourself not expensive , it costs 45 minutes a soldering iron , some ledsolder and a middele size philips screwdriver and 15 elco's witch costs 10 cents ( euro ) a piece approx .

but since they are already modified ( lights on the front ) they could have the elco change already . original they are blue with philips on the side printed .

good luck with the repair , greets mattie

@ herman t akes kan niet in dit bericht het wordt dan sijbrand ????

[Zapper]

MFB speakers can be chained to get more power.

The original state is that a 2-coax din cable goes from preamp to input of one speaker, and then another din cable interconnets the speakers. With the switch on the back you can select right or left channel.

You can interconnect more of them using every time the output plugs.

The have a red indicator (not blue) and they need some signal on the input to switch them on.

Inside you will find a relay. Eventuelly you can try opening the relay and pressing it manually to see if the speaker works. Look out, do this only short time to try.

If it works, your entry pcb is broken (contacts) or the elco of the input switch on circuit dried out.

In old stuff many time the small electrolytic caps are dried out. thos 4.7uF, 22 uF e.g.
The bigger ones often are good, also the axial caps from philips were very good.

[analogadikt]

Thank you mattie and Zapper for the responses.

I was able to locate the fault to a dry solder joint of the blue wire connecting one of the two big capacitors. Repaired that joint and both speakers are live now. But the sound output is low and distorted. I require SERVICE MANUAL. Where can I get that?

Regards,

analogadikt

[piet2401]

Hello go to the menu on the left.
Tab "luidsprekers"--> (e)Motional-->series II --> 22RH544 there you will find the manual underneath Servicedocumentatie:

[mattie]

try put some contactspray in the switches on the back , also makes it difference if you wiggel the dinconnector on the back? if so place the din in the output connector ( its the same connection ) and solder the input din .

if its not better than , the chance is high that this is caused by elco's in the signalpath that are dry and need replacement .

the manual is downloadable here http://www.mfbfreaks.nl/html/main/sitemap.htm.

greets , mattie

[analogadikt]

Thanks again.

I had tried contactspray but that did not help.

The caps are original. The back panel says TROPICALIZED but I agree with the suggestions regarding replacing them.

Regards,

analogadikt