[Jason Gin] recently wrote in to tell us about his adventures replacing the eMMC storage chip on a cheap Windows tablet, and we have to say, it’s an impressive amount of work for a device which apparently only cost him $15. Surely much better pieces of hardware have been tossed in the trash for less serious failures than what ailed his DigiLand DL801W tablet. We’d love to see the lengths this guy would go to restore something a bit higher up the food chain.
As any good hacker knows, you can’t fix the problem until you understand it. So the first step [Jason] took was to conduct some troubleshooting. The tablet would only boot to the EFI shell, which didn’t do him much good since there was no on-screen keyboard to interact with it. But he had the idea of trying to connect a USB keyboard via an OTG adapter, and sure enough that got him in. Once he was able to enter commands into the EFI shell, he attempted to read from a few different sectors of the eMMC drive, only to get the same nonsense repeating data. So far, not looking good.
But before he fully committed to replacing the eMMC drive, he wanted a second opinion. Using the same USB OTG adapter, he was able to boot the tablet into a Windows 10 environment, and from there got access to some drive diagnostic tools. The software reported that not only was the drive reporting to be half the appropriate size, but that writing to the chip was impossible.
With the fate of the tablet’s Foresee NCEMBS99-16G eMMC chip now confirmed, [Jason] decided it was time to operate. After pulling the tablet apart and masking off the PCB with Kapton tape to protect it from the heat, he slowly went in with his hot air rework station to remove the failed chip. But rather than put another low-end chip in its place, he used this opportunity to replace it with a Samsung KLMBG4GEND-B031. Not only does this chip have twice the capacity of the original, it should be noticeably faster.
With the new Samsung eMMC chip installed, [Jason] put the tablet back together and was able to successfully install Windows 10 onto it. Another piece of tech saved from the big landfill in the sky.
If the casual confidence of this particular repair wasn’t enough of a clue, this isn’t the first time he’s showed some unruly eMMC chips who’s boss.
Has reflowing surface mount components got you down? [Giorgos] is currently working on a project that will lift your spirits…. well at least your hot air gun. Tired of manually holding his heat gun in one hand and IR thermometer in the other, [Giorgos] set out to create a device to alleviate just that. Although not completed yet, it appears the machine’s intent is to hold the heat gun at an appropriate height above the work piece in order to achieve the correct reflow temperature. He doesn’t say how the height of the hot air gun will be controlled. We’d like to see a microcontroller adjust the height of the hot air gun depending on the temperature of the component to be reflowed. [Giorgos] gives an extremely detailed account of his build process. Make sure to check out all four pages of the project post!
We’ve seen a lot of interesting work from [Giorgos] over the years like this capacitive touch-pad entry system.
[via Dangerous Prototypes]
This hot air rework station is being used for more than just soldering surface mount components. Since it has settings for temperature and airflow [BrokeHippieTech] figured it would work as a bag vaporizer. In the video after the break they show off the custom parts and then take it though and herbal blend bag fill.
The hot air station comes with several different tips. The smallest one was used to mount a vaporizer bowl using high-temperature JB Weld. On the output side of the bowl a metal stem was also affixed to interface with the mouthpiece of a vaporizer bag. The heat from the rework station brings the herbs just below the combustion point, releasing the active ingredients without including the harmful byproducts associated with smoking.
We’re putting this one under medical hacks because we hope it’s being used responsibly and legally. As with the last vaporizer build we looked at, we have concerns about what else the apparatus may be putting into the collected gases.
Continue reading “Hot air rework doubles as an herbal bag vaporizer”
The $10 “fire-starter” is the most common beginner soldering iron. These are simple irons with a hot end, a handle, and little else. There’s no temperature control or indication. Despite their simplicity, they’ll do just about anything. You can solder any legged chip type with this type of iron. We used fire-starters in the lab for years.
Eventually, we wanted a hot air rework tool to salvage SMD parts and solder QFN chips. Aoyue is a relatively unknown Chinese brand that makes soldering stations very similar in appearance and function to Hakko. Aoyue stations are recommended and used by Sparkfun Electronics, something that factored heavily in our decision to buy an Aoyue. Read more about our experiences with this tool after the break.
Continue reading “Tools: Aoyue 968 3-in-1 soldering and rework station”