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#electronicsrepair

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New day - new Raspberry Pi brought back to life 😃

This one probably fell down because it had no shorts, all voltages from DA9090 were present, but it didn’t start most of the time - it did once but then I spent quite some time trying to figure out where is our issue.

Reflowing CPU and RAM chips must have helped ✅

Wow, this was a surprisingly detailed article about how to fix a jumpy mouse scroll wheel by fixing or replacing the encoder.

Unfortunately, I do not feel up for this right now actually. It's cool to know it's possible though.

makeuseof.com/fix-mouse-scroll

MUO · How to Fix a Mouse Scroll Wheel Jumping Up and DownMouse scroll wheel jumping up and down and making control difficult? Here's how to fix it.

So my #Bosch #Intuvia display started to fail to wake up the battery/motor on power on. Its still possible to press the button on the battery to wake it and the motor up but... eh.

Now it got a new smol LiPo. It lasted 25000 km / 1990 hours / 10 years so not bad.

25007 / 1990 hours - thats way too slow? Yes, it counts the time on the charger as well so this is ride time + charge time = total on time (minus the time where I charged the battery directly / not in the bike).

Something a bit different - a #Raspberry Pi #CM4 with a CM4-NANO-B carrier board by #Waveshare.

Customer accidentally put this assembly on a metal surface and it did got shorted.

DA9090 PMIC was dead and had been replaced, but it took me quite while to figure out how to make it work again - see the thing is that when you flick the switch on a baseboard CM4 won't turn on. You have to power the whole thing down, flick the switch to ON then then power it 🤦🏻‍♂️.

Continued thread

But this time I was finally ready - I received this large universal reballing stencil from AliExpress where the first 18x18 option fits the RP1 perfectly.

So instead of reflowing again I just took it off the board, reballed and soldered nicely.

After letting it cool down for 10 minutes next to an open window it works as it should now 👍.

aliexpress.com/item/4001204908

Continued thread

There also was a Raspberry Pi 5 with ripped capacitors of the RP1 chip. Without them Pi would not start and would not even get the firmware updated.

I restored those and later covered all of that with UV mask.

But that wasn't enough - had to also reflow RP1 chip because its contacts were damaged too.

This customer was really lucky because that not doesn't always work well, but it did this time.

Interesting Raspberry Pi repairs today.

First - Pi 3A Plus. Clear burn marks and dead short on a 5V rail.

Usually it's the diode, so I didn't even check it - just got it replaced.

And - surprise - it was not the diode 😂. It turned out to be a 50 uF capacitor right next to it.

A nice and easy fix - one more happy customer ✅

Okay, I'm sending out a call for help. I'm trying to repair my soldering iron, after I turned it on one day and it went "POP" and wouldn't heat up.
I located the damaged part, a transistor that is half missing.
I can't identify the part however. All I can make out is "A6" and "322" on the part.
Help me Mastodon, you're my only hope!
#ElectronicsRepair
#electronics

But it's not all failures. Some other customer sent in his NanoPi NEO 512. It a was nice, fast and easy fix - MP2143DJ IC got hot up to 150+° C, so I ordered and replaced it right away ✅.

Again - life is so much easier with schematics:
wiki.friendlyelec.com/wiki/ima

And here's a datasheet for that part:
monolithicpower.com/en/documen

Someone sent me an Orange Pi 5 Pro the other day for repair and sadly I was not able to fix it, thought the issue was quite obvious.
RK806-1 PMIC not only blew up - it catched fire and welded itself to the board so badly that I was unable to remove it. It also took an SY8089AAC with it.

How did that happen? He used a DC-DC step-down converter. No idea why and how, but I''d avoid using those converters at all costs.