GrahamH's photos with the keyword: fault

Repair Amplifier 20220818 14 42 20 Pro

17 Apr 2023 2 2 191
This is one of three amplifiers at the church I go to. I was gathering interconnection information for the whole system so I could make changes to improve reliability in Toowoomba's summer thunderstorm season when I found this had stopped working. I removed it from the equipment rack and took off the cover. There was nothing obvious except the blown fuse in the mains power socket. This photo was taken then. I replaced the cover and took it home for further investigation. At home I eventually decided that the mains power transformer, the circular object with the wires going from it, was probably faulty. I contacted the Australian agent of the manufacturer, Bosch, for circuit diagrams and technical information. They weren't very helpful but did refer me to a business which did warranty repairs for this type of product. The service manager answered some general questions but didn't/wouldn't supply any circuit information. I worked out a likely AC supply voltage but didn't anything on hand to provide it to check that the rest of the amplifier was working correctly. I ordered a replacement transformer anyway with some trepidation. A pleasant surprise was that it was priced comparably with the normal pricing for similar transformers. About a month later the transformer arrived. With the aid of some photos, a soldering iron and some other tools I replaced the transformer and was relieved when the amplifier then worked correctly. I measured a few key voltages and wrote them on the chassis in case there was any further trouble. The amplifier worked correctly when reinstalled in the rack at church. Mouse-over to see some other photos of the amplifier.

Inspiron15R 5520 58crop

29 Nov 2015 1 2 266
My wife's 3-4 years old Dell Inspiron 15R 5520 laptop failed. The power pack is shut down when it is plugged into the power socket, but otherwise works ok. I opened the laptop and found dried gunk and brown deposits and stains around a partly destroyed SMD. See note. I cleaned most the mess, as shown here, reassembled it but the fault remained. Tomorrow, Monday, I'll contact Dell Australia about parts, boards and new laptops. November 2015.

Inspiron15R 5520 57crop

29 Nov 2015 295
My wife's 3-4 years old Dell Inspiron 15R 5520 laptop failed. The power pack is shut down when it is plugged into the power socket, but otherwise works ok. I opened the laptop and found dried gunk and brown deposits and stains around a partly destroyed SMD. See note. I cleaned most the mess, as shown here, reassembled it but the fault remained. Tomorrow, Monday, I'll contact Dell Australia about parts, boards and new laptops. November 2015.