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
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
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.
Dom
2x BeoSystem 3, BeoSystem 5000, BeoSystem 6500, 2x BeoMaster 7000, 2 pair of BeoLab Penta mk2, AV 7000, Beolab 4000, BeoSound 4000, Playmaker, BeoLab 2500, S-45, S-45.2, RL-140, CX-50, C-75, 3x CX-100, 3x MCL2 link rooms, 3x Beolab 2000, M3, P2, Earset, A8 earphones, A3, 2x 4001 relay, H3, H3 ANC, H6, 2014 Audi S5 with B&O sound, and ambio
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.
It's not uncommon to see one of the rectifier diodes shorted.That will also blow the fuse.
Martin
You are right inhere, did the testing here at my work and one of the diodes did give a false signal which indicate it was not working. The testing of the capacitor was not done because the 4700uF was way out of reach of this testing tool.
Did have a master where the 4700uF was increased to 6900uF last week.
Soldering braid and suction bulb's will float or break your traces at some point. Not my thing. A desoldering station here for daily use.
Saves time and prevents floating or broken traces.
Replace the relais if your using passive speakers.
Like to know:
No, sorry I haven't. It was brought in with another fault and replaced the capacitor after measuring.
All these Roederstein caps have the same symptom, they lose contact at the centre solderjoint due to the heat. Hardly visible, but is there, a broken solderjoint. So it must make a difference.
If used a type snap-in from Rubycon if I remember correctly.
I have the luck here at my work lots of experienced electronic guys are around so they did show me another trick to give a indication if the ROE is wrong.
Nothing broken on the ROE capacitor, but still I'm going to replace it by the Panasonic. Be aware that the tripot on the ROE does have a function, without resonation could occur, that why I think Onkyo has used epoxy in my vintage receiver. Think I'm going the same for the two leads capacitor.
Like to know another thing, can I replace the missing glass panel by a plastic one, like LEXAN or plexiglass???