Warning<\/strong> \u2013 this gets technical and requires some knowledge of electronics and soldering but it\u2019s really not difficult and you can have your Beomaster\u00a0working again in a couple of hours or so. As with any mains powered device always follow manufacturers instructions and Never<\/strong> operate your Beomaster with the top open and connected to mains power. I cannot be held responsible for any damage or injury you may sustain.<\/p><\/blockquote>\n Bang and Olufsen’s Beomaster 3000 tuner amplifier is an impressive design but requires large high value\u00a0electrolytic capacitors and uses fragile preset potentiometers that fail with drastic results.<\/p>\n Blown fuses<\/strong> – If the mains fuses blow the most likely suspects are the three large tubular capacitors. An ohms check can indicate if this is the case – a steady resistance of a few ohms indicates a failed capacitor, although they can breakdown only when voltage is applied and pass the ohms test. It’s best to disconnect a wire from each to isolate the capacitor and measure its resistance without the rest of the circuit connected. Note the polarity (+\/-) on each wire to make sure each electrolytic is reconnected correctly. Damage will result if these electrolytic’s polarity is reversed.<\/p>\n The slightly larger capacitor is a 5000\u00b5F \/ 70v main smoothing reservoir. It should be replaced with at least 4700\u00b5F. Modern electrolytics are much smaller so it’s possible to choose a higher value and higher voltage rating and it still fit. Make sure the capacitors can cope with the ripple current so they don’t overheat. I prefer increasing the value to at least 6800\u00b5F or 10000\u00b5F\u00a0\/ 100v rating and 85\u00baC working temperature with screw terminals. If you want to retain authenticity keep the original value.<\/p>\n The right and left amplifiers use a 3000\u00b5F coupling \/ blocking capacitor located either side of the main reservoir. These are rated at a lower 35\/40v as the output stage sits at around 30v – half the 60v dc supply. But the audio signal will swing to near 60v when driven hard so I suggest replacing both with 4700\u00b5F rated at least 63v. Higher voltage components are physically larger so will be closer in size to the originals and fit. Replace both even if just one has failed. See end of post for examples of leakage.<\/p>\n With all three capacitors replaced with luck it should switch on without blowing the fuse.<\/p>\n If not there are few few other PCB mounted components such as the skeleton presets and smaller electrolytic capacitors that will need investigating and will be the subject of another post. In the meantime if you are tempted to replace the smaller electrolytics\u00a0make sure you observe the polarity of each before removal to ensure it’s replaced the right way around. I suggest marking the negative with a black dot from a Sharpie marker pen and take a photo before you start!<\/p>\n BM3000-2 Main Amplifier PCB<\/p><\/div>\n <\/p>\n BM3000-2 Left Channel Schematic<\/p><\/div>\n BM3000-2 Right Channel Schematic<\/p><\/div>\n BM3000-2 Amplifier Capacitor Replacements<\/p><\/div>\n BM3000-2 Left Channel Amplifier Capacitor Replacements<\/p><\/div>\n Check out other comment on the Beomaster 3000-2 here BANG & OLUFSEN BEOMASTER 3000-2<\/a><\/p>\n Here are some examples of the original electrolytic capacitors that have been replaced showing evidence of leakage. Click to zoom.<\/p>\n\n\t\t![\"RearMains\"](\"http:\/\/storycase.co.uk\/radio\/wp-content\/uploads\/2013\/12\/RearMains.jpg\")
<\/a><\/p>\n<\/a><\/a><\/a><\/a>Electrolytic capacitors<\/h3>\n