I am trying to fix a broken “Turtlebox” speaker for a friend. I found several popped caps, but ran across something odd on the PCB. Does anyone know what is is? Thanks in advance!

 

what exactly you are referring to?
i see remains of an alu cap that blew up. only electrodes going through rubber seal and a blob of glue remain

 

Thanks! I was wondering if that was the case. There are 3 more popcorned 1000uF electrolytics on the PCB. Is there any way to determine what the value of that cap was? The shell is nowhere to be found. Also, what are the chances other things are blown up on the PCB - chips or other? Is it worth trying to replace these caps and see if that fixes it? Thanks in advance!

 

Probably the same value as the un-popped one next to it.

 

Make sure you check the diodes in the power supply as something must have caused the cap to go bang!

 

what exactly you are referring to?
i see remains of an alu cap that blew up. only electrodes going through rubber seal and a blob of glue remain

I don’t see that at all. the black cylinder that the terminals are sprouting from looks undamaged to me. And the white blob looks like adhesive, not the insides if a blown cap.

Were there wires connected to those two terminals?

 

It looks like an explosive electro launch to me. All the trash left behind looks like electrolytic cap innerds and the case is somewhere in orbit. Something has caused the cap to explode so that needs to be investigated. But a better focused picture would be a help. My old Android phone camera has a macro setting and that is good for this sort of thing.

 

Exactly...

 

I don’t see that at all. the black cylinder that the terminals are sprouting from looks undamaged to me. And the white blob looks like adhesive, not the insides if a blown cap.

Were there wires connected to those two terminals?

The fiber is the liftoff residue. The terminals were connected to foils inside the cap.

Typical cap launch.

 

The fiber is the liftoff residue. The terminals were connected to foils inside the cap.
View attachment 319882

Ah, that makes sense.

 

<Memories of youthful launches of caps with a 24V transformer when there “wasn’t anything else to do”.>

 

in fact it is a good exercise to blow up some parts on purpose and experience first hand what the failure modes look like.