Electronics help needed Please.

[twm.bwen]

Hi there, I've got a faulty set of active speakers. When turned on they just hum and there's no audio output. I replaced one of two fuses (t3.15AL) on the pcb that has two large capacitors on it. It blew immediately but that may be because I replaced it with a F3.15AL.
I'll try and get the T3.15AL that is says on the pcb, but assuming it blows again. How do I acertain the cause of it blowing, which component is faulty. I'm assuming it must be one of the large cpacitors.

Thanks
TOm

 

[jefoss]

try the electrics forum, those guys will know how to help

 

[Yarn]

If internal fuses blow on a PCB, it is generally a bad idea to replace them without wondering why the fuses went in the first place. You say you used the right current rating, ok the F in the fuse that you used was a fast blow, but that should unlikley make a difference.

The large capacitors are most likley smoothing for the power supply these decouple AC ripple on the recified DC output of the power supply, which will then be fused.

It could posibley be the capacitors, but unlikley IMO. It is more likley a fault with the circuit that the power supply is feeding. I would expect the fuses to be after the capacitors if they were PSU fuses - 2 fuses due to stereo amp. But they may be protection fuses for the audio output.

If the problem is not obvious, your best to move on and forget these speakers for your own saftey.