Repairs
This category covers real repairs, usually broken units bought cheaply on eBay or picked up as a return, with the fault unknown at the start. The point is the diagnosis: tracing a fault back to a specific component using a scope, a multimeter, and schematic knowledge, rather than jumping straight to a part swap.
Expect amplifiers, audio equipment, and general household electronics with genuine faults, not staged teardown content. Where a repair doesn’t succeed, that’s shown too. Not every unit comes back from the dead, and the process of finding that out is still useful.

SDG #368 Tricky Repair: Cambridge Audio Bluetone 100 - No Bluetooth
Diagnosing a Bluetone 100 that plays analogue audio but won't pair. Scope traces, EEPROM dumps and a CSR8645 to CSR8675 module swap that finally works.

SDG #363 eBay NAD Direct Digital Amplifier D 7050 Repair - Lots of issues
Repairing a faulty eBay NAD D 7050 digital amplifier: cracked SMPS transformer, dead caps, blown OLED boost converter and a burnt out white LED.

SDG #356 Repair of an Amazon Return Shinco Dehumidifier SDL5-10D
A faulty Shinco SDL5-10D dehumidifier bought for £5 as a customer return, diagnosed and fixed: blown display driver IC and an open-circuit resistor.

SDG #355 eBay Fosi Audio N3 Portable Bluetooth Headphone Amplifier Repair
A £4 faulty Fosi Audio N3 Bluetooth headphone amp gets a dead-channel diagnosis, ripped 3.5mm jack replacement, wire mod and LED fix, plus a listening test.

SDG #353 eBay Cambridge Audio DacMagic Plus Repair - High pitched whining noise from output
Diagnosing the DacMagic Plus high pitched whine: the real culprit is C179 on the DC-DC input, not C148. Full ESR testing and repair walkthrough.

SDG #351 eBay NAD Hybrid Digital Amplifier D 3020 V1 Repair - Won't power on (Hypex UCD102 Class D)
Fixing a no-power NAD D 3020 hybrid digital amp: open current sense resistors, shorted Class D MOSFETs and glue-corroded vias on the Hypex board.