Uploaded June 2026 | Updated September 2026, 1 hour ago

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Well it seems plenty of you guys liked the Fault Finding Masterclass video where I traced a fault down to a tiny component just using datasheets. Here is a different example, it's an amplified speaker and it makes horrible noises when switched on, but works OK once it warms up. Here are some techniques to help you find this sort of fault, and yes I DO fix the fault in this video. I'm thinking of making a ad-hoc series out of this idea, as and when I find real life faults that need different techniques, put them all into a Masterclass playlist together to make them easy to find. Let me know what you think...

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Equipment used in my videos. These are affiliate links, you pay the normal price and I make a small commission.

DM40C
https://s.click.aliexpress.com/e/_c4q1dFy7
Aneng AN870 (Same as Zoyi ZT219)
https://s.click.aliexpress.com/e/_c2wcOv9N
Zoyi ZT-DQ02
https://s.click.aliexpress.com/e/_oB2u3sT
WinAPEX 268B Clamp Meter
https://s.click.aliexpress.com/e/_opJTjEP
VC480C+ MILLIOHM METER
https://s.click.aliexpress.com/e/_onE0FaJ
MESR-100 ESR METER
https://s.click.aliexpress.com/e/_oombcej
XC6013L CAPACITOR METER
https://s.click.aliexpress.com/e/_omnOxub
FNB58 USB ANALYZER
https://s.click.aliexpress.com/e/_c3hysTXt
4KV Breakdown Tester
https://s.click.aliexpress.com/e/_omKXmND
LED Backlight Tester
https://s.click.aliexpress.com/e/_oCRPzdl
NI-210SC Curve Tracer
https://s.click.aliexpress.com/e/_o2e0Par
NI210SJ (cheaper option but watch my review)
https://s.click.aliexpress.com/e/_oD60O0D
PCI POST ANALYZER
https://s.click.aliexpress.com/e/_c44XQKaj
FNIRSI 1014D SCOPE
https://s.click.aliexpress.com/e/_c2xAnnbv
NPS3010W 30V 10A PSU
https://s.click.aliexpress.com/e/_oDuHLdl

Nice-Power Dual 120V 3A PSU
https://s.click.aliexpress.com/e/_okGvYQ7
HR1520 Pro Short Killer
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KSGER T12 Soldering Station
https://s.click.aliexpress.com/e/_omqBjWR
AIFEN-A9 PRO Soldering Station C115/C210/C245/C470
https://s.click.aliexpress.com/e/_ongFBEJ
C470 Soldering Iron & Tips
https://s.click.aliexpress.com/e/_opm1OND
https://s.click.aliexpress.com/e/_oDVNACf
QUICK 861DW
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PROS'KIT SS-331H
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Sequre HT140 Hot Tweezers
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KADA 853B Preheater
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FNIRSI SWM-10 Spot Welder
https://s.click.aliexpress.com/e/_ooZey3t
INFIRAY P2 PRO IR CAMERA + MACRO LENS
https://s.click.aliexpress.com/e/_ootcxPv
TOOLTOP ET13S THERMAL CAMERA METER
https://s.click.aliexpress.com/e/_c4MMdodZ
ET13S MACRO LENS
https://s.click.aliexpress.com/e/_ol9d8hh
Trinocular Microscope
https://s.click.aliexpress.com/e/_okJictD
TOMLOV TM4K AF FLEX
https://s.click.aliexpress.com/e/_oBirts7

TL866 II+ PROGRAMMER
https://s.click.aliexpress.com/e/_c32XDS1D
NC-559-ASM FLUX
https://s.click.aliexpress.com/e/_onMlHRD
DESOLDER BRAID (I use size 8045)
https://s.click.aliexpress.com/e/_onhlLkx
HX-T100 SOLDER
https://s.click.aliexpress.com/e/_o2DHwJH
ESD-11 TWEEZERS
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Richard