I’ve never ventured much into TV repair, but a friend of mine who works at a tire shop uses this TV at lunch break, to play some games with colleagues. However, it started developing an issue where it suddenly would start “rebooting” by itself.

He asked me if I could take a look at it, and sure enough, he brought it to me.

I started verifying the usual suspects: Some capacitors with elevated ESR were replaced. Voltages were good. No broken MOSFET’s. No failing diodes. No abnormal hotspots. Really a random issue.

I factory reset the screen, and still nothing. From time to time, it does it. It just restarts the panel.

And then while tinkering, I just displayed a white background, and it remained on. For a long time! So I messed with the menus a bit and noticed that the brightness of the panel was constantly changing. In such cases, the screen would start rebooting. So it must be something with the PWM driver.

However, information on these devices’ internal workings is scarce, but I did find a way to disable the PWM… Lo’ and behold: there’s a PWM pin that gives feedback from the mainboard, to the power supply.

Do you see it? Pin 2 - Called EPWM. I just disconnected it, and taped it with some Kapton tape to the wiring loom.

I’ve had an Ikea Trådfri LED1836G9 fail, and I wondered what would be wrong with it. It just dropped from my Zigbee network, and re-applying power did not change anything. Would it be the LED’s? Just a simple fuse? Let’s dive in.

To take these apart, just apply some gorilla-strength and pull apart the milk white dome from the body of the housing. You’re then greeted by a removable LED-board, held in place with some screws. Nice construction. All modular.

The power supply can be removed as well, without damaging anything. It’s amazing that something that is considered “disposable”, has such a nice, repairable construction. Well done Ikea.

However, the power supply board immediately gave away its secrets:

I recently acquired an Anbernic RG35XX-H to play some retro games for some old systems I own. But since my A/V setup is all nicely tucked away in a rack, so nothing is visible inside our house, I needed something to play these “on the go”.