[JohnAudioTech] noticed there was no bass on the TV at his parents’ house. That led to the discovery of a blown fuse and a corresponding repair. When he opened it up, he could smell that something had gone on in the amplifier. You can follow the repair in the video below.
His first theory was that some glue became conductive and shorted the power rails. We were skeptical, to be honest. When he fed power to it through a current limiter, he could hear a sizzling noise and even see a little glowing from the hot component.
Disassembly ensued. Removing the suspect components showed some seriously burned components and some charring under a switching transistor. The capacitors looked much worse for wear, and the PCB needed some wires to jumper burned conductors.
At the end, there was thumping, so it seems the surgery was a success. However, testing blew a fuse again, which made us nervous. Still, seems to work if you don’t drive it too hard.
We always enjoy watching a teardown, and if there’s a repair too, that’s even better.
FSM damn it – first it’s “A Fun Action Generator From The Past” and now a “Tasty subwoofer …”. Dunno what’s wrong but the HaD titles aren’t at fault. ;-)
I don’t buy the adhesive being the reason for the failure. That looks like a leaky cap issue. Should have done it right and shotgunned both caps and used the right fuse.
At least it’s working.
Yeah, I also suspect that the dead cap leaked and cause board to arc. It was too close to the rectifier and got cooked. That type of glue can definitely become conductive and arc though.
For the parents?
No.
Buy a cheap new ClassD subwoofer amp and ‘rewire it’.
I did a little Googling on ‘V1020 subwoofer’
This thing is $252 new on Amazon. 10 inch sub.
Claims 160watts rms, but photo in FA shows it only draws 100!?
Well worth repairing, speaker capable of being the key part of a perpetual motion machine.
Just not for the parents…
Put in new amp and take burnt one for free power project, Profit!
I fixed one like that one it had zeners for the plus-minus supply till they cooked off the board and the rest survived.
Nice to see John Audio Tech getting a shout out! He had like 100 subscribers when I originally came across the channel, he does put the effort in, so glad to see his stuff is spreading.