Here is my workbench topic

16 replies

Problem I had was a blow-out fuse F3 on my actual Beomaster 4500 and I could not find the cause inhere, yes afraid by the lack of experience of electronics, did stop me from getting the root cause of this problem. But then the opportunity came to buy a cheap, optical damaged  but with a working amplifier Beomaster 4500, so I combine the two Beomasters to one that was working and not damaged nor scratched Beomaster.

 

That did leave me with a left over the was not working, full of scratches/dents on the metal, no glass and broken plastic top.

 

dent and scratches on the metal

 

Broken plastic ribs, sorry but you have to click on the picture to see more Erm..

 

 

de-soldering of components that could be the cause inhere, the ROE capacitor and the diodes. 

 

 

Ready for testing at my work, sorry picture made by my old Nokia.

 

 

A handy for de-soldering a woven lead made by copper.

 

 

Sorry I have to leave now, but I will publish more and rewrite the postings done here.

I've had more success with desoldering braid than with a suction bulb. What's your experience and preferred method?

I only have experience using this woven copper lead. It does work great BTW.

Problem: blowout  fuse F3, replacement fuse was also blown out.

Noticing:  hard plop sound on the speakers when connecting the Beomaster to the main power 230Volt supply. Burn spot on the rectifier print board near fuse F3. 

First action: disconnect every plug on the amplifier print board, remove fuse F2 and F4 [shut down 33 volt system], changing from 220volt to 240Volt on the primary, see picture here.  NO EFFECTS

Next action: The suspected burned print board from the rectifier: removal of the Diodes D10, DD17, D19, D27 and the ROE capacitor. These will be tested at my work, changed by new ones, only the 4700uF ROE seems to be not available anymore, so this will be exchanged by the Panasonic FC.

 

Here a picture with the burn spot on the print board.Maybe I also remove the white capacitors [C5 & C37]  seeing that burn spot, lot of heat going from diode to the print board. The new diodes of the rectifier will be soldered 10mm above the printboard to give the diodes more cooling.

 

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