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Massive ripoff attempt on next door neighbour thwarted

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nctnico:
Over here practises like that are common for lock smiths, plumbers that deal with emergencies (broken water pipe) and sewer blockage services.

Gyro:
OTish, but it looks as if that board cooks, particularly around the bridge rectifier diodes (and contributing to the regulator temperature). It might be worth suggesting that any ventilation slots aren't obstructed.

KE5FX:
Yeah, those diodes got hot enough to scorch the PCB and boil the capacitor sitting practically on top of them.  Diabolically clever engineering in a planned-obsolescence sense, and diabolically stupid in all other respects.

Usually when a 78xx regulator fails dead short, it's because there's more energy storage downstream than upstream.  Was the large capacitor good in the sense that its capacitance was still within tolerance, or was it just good from an ESR standpoint? 

If the smaller capacitor next to it is 100 uF or so, and the input bus had another load that discharged it in a hurry at cycle-off time, that could make life rough for the 7812.  I'd put a diode across it before giving it back.

Someone:

--- Quote from: Gyro on November 27, 2023, 01:57:27 pm ---It might be worth suggesting that any ventilation slots aren't obstructed.
--- End quote ---
Reading a product manual with completely serious instructions like "keep a 30cm open space on all sides of the appliance", for a fridge. Hopefully dishwashers aren't as picky even though they are installed almost identically in kitchen cabinetry.

langwadt:

--- Quote from: ataradov on November 27, 2023, 07:23:38 am ---Sometimes it is easier to name a price no reasonable person would pay rather than explain why you don't want the job. And if they pay, oh well, you will make some money.

--- End quote ---

and I can see why a pro that is going to be on hook for the result wouldn't want to bodge something together unless they get paid really well

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