EEVblog 1657 - DUMPSTER Samsung 75 inch QLED One Connect TV

[EEVblog]

Almost 30 minutes of tearing down a Samsung 75" QLED One Connect dumpster TV and trying to power it up to see if it's busted or not. QA75Q7FNA

00:00 Dumpster Samsung QLED 75"
04:46 - Teardown wasn't easy as expected...
08:11 - What is this cable retention BS?
11:26 - I'm still at it...
14:22 - Where's Wally? Follow the voltage.
17:26 - Where do I get 350V DC at a few hundred watts?
21:21 - DIY 350V DC power supply
22:52 - 350V DC right up the clacker
24:19 - I need MORE voltage

[EEVblog]

Looks like it's dead, or at least very sick. Someone on Twitter said the UV backlight LEDs are conoverted to white through the quantum dot film.
Definitely not worht spending money on.
https://www.youtube.com/shorts/sZl_1bxqeic

[Bud]

So make an educational video on quantum dot film then. No good crisis should go to waste.

[jnk0le]

diffuser cracks + reflector warping?

https://www.rtings.com/research/thin-lcd-tvs-break-faster-under-prolonged-use

Doesn't look like any of the LEDs completely failed. If it lights up without mobo, then it should display the "no signal" (or something like that) with. (but that's for the designs with no extra boxes)

[langwadt]

seems like there's an editing error around ~5:15   

[braddr]

I'm curious what the outputs of the supply board showed with the low input voltage.  Assuming the others are right about accepting a wide range of input values, the outputs might have been correct.  Alternatively, ignore inputting the input voltage and use power supplies to just generate the output values and bypass the board altogether to test the other parts of the system.  Might help figure out how much of the whole thing is working correctly and tell you more about whether it's worth moving forward.