this post was submitted on 02 Jul 2025
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I have a controller for an electric throw blanket that I would like to repair, but I have no experience soldering on boards

You can see at bottom left a yellow box and a resistor. Something has burnt out in this area, and likely both will need to be replaced at a minimum

I would also need help identifying parts. The yellow box is embossed 'Tenta' and has printed on the side 'TC MEX/TENTAMKP 0.1 uf 275VAC' with some other markings obscured or damaged

Is this an achievable project?

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[–] ThePyroPython@lemmy.world 33 points 2 days ago (7 children)

Jesus, this isn't a slight against you OP but as an electronics engineer I feel I need to have a rant about the shoddy design here:

First of all, I have no idea what that component is dangling off the burnt-out through-hole resistor is or why it's there.

Surely it can't be a part of the temperature control loop, so I would guess it's a thermal fuse to shut off the blanket if that resistor burns because it handles power to the heating element.

If so, what THE FUCK were the designers thinking?! Couldn't afford even a small power resistor with a heatsink and a cheap thermocouple to a temp sense IC?!

Nah it'll be ok, either it burns out the resistor and the customer is not injured or the customer's house burns down. Either way no deaths, just complaints about our shitty build quality.

Second, they're using WAY too much solder for these surface mounts components.

And third, why has R16 shifted from it's pad? Bad soldering job from too much solder? Bad placement from the PNP machine? Or, god forbid, something gets hot enough to cause the solder under that resistor to start melting?

It's genuinely shocking the amount of stuff that's just being allowed to be sold these days.

If you can't get the blanket repaired OP, please consider sending this to Big Clive as he'd have a field day with this.

[–] pezhore@infosec.pub 9 points 1 day ago (1 children)

Am I also seeing heat shrink tubing that hasn't been heat shrunk?

It self-shrinks when the board catches fire

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