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
Hissing noise from amp, (Penta speakers checked fine) , capacitor exploded on the same circuit board left side where speakers plug in bottom PCB board, 3 speaker channels working not 4.
Hi i have the above unit with CD player, tape, radio tuner. I plugged in the unit and a vibration noise it just sounded like the power supply had gone faulty B & O 8013362 and i turned it off quickly checked the fuses inside all ok. I can hear the relay switching on when i plug it in. I plugged the unit back in and it started smoking oh dear. Then a small explosion, a capacitor exploded. I do not have electronic, scope, or know what to do, very technical know how, but i will have a bash at fixing it myself. Firstly i have a resistor set up with two wires, to discharge any capacitor, before i check it. Secondly i have a capacitance tester unit (on order not arrived as yet), A good place to start, only cost a few pence for caps, before i decide power supply is clapped. Or full unit bin job.
Where do i buy the capacitors from ? I would like a kit. Plus the 2 caps 10000MFD near the power supply. Can i go to any electronic shop Maplin? Reading the research i was informed that only Philips capacitors will work, if you use any other make, the unit will not work. Lastly I have found a transistor burned out on the heat fins at the back of the unit, it has a metal clip on it, and white heat paste it looks like the metal fin has burned off. So on inspection (heat fins at the rear of the power supply) i need a transistor do not know what value it is it is fried, It is transistor number 5 counting from left to right (middle one), it has 4 legs on it. On inspection the transistors have Philips on them also, where do i get the transistor from? Do i have to use Philips only? If this does not solve problem can i get the power supply if i need it, new, or will it be big money. If it cost a lot to fix i will buy another amp. Thanks for all readers help.
Upgrade to silver or gold membership and you will be able to access the service manual. You don't need to use Philips caps. Only in the CD player there is one particular cap where the same type Philips is recommended.
The trimmer pots for the idle current are up for replacement as well.
The vibrations, I believe, could very well be due to the large 10000mF caps being bad.
Martin (Dillen on site) can usually provide capacitor packs for most receivers. I would ask him as he will provide the right type and instructions!
Peter
I don't normally come forward offering direct help, but as I don't live a million miles away I will be happy to take a look at the amplifier for you. Maplin sell Electrolytics but I am not sure what make, and they won't be the cheapest in town! As above Martin offers full kits but tbh I think you will whistling in the wind with the symptoms you mention above, ALWAYS best to get the thing running before going for a mass recap, besides most will be fine in this unit! the master has faults that will require investigation with more than a capacitance meter too!What ever happens please don't throw it away, someone could find use for the parts that haven't died if nothing else!
Olly