Computer Hardware

Recording a Raspberry Pi desktop using a HDMI Video Capture device and OBS Studio

(May 27, 2021) How do we record HDMI video? Does recording HDMI video require expensive gear? It turns out the HDMI output from a computer can be easily recorded with a cheap HDMI video capture device costing around $25.

Monitoring SSD drive health

(November 19, 2017)

SSD drives are awesome, they're fast, they consume little power, they're light weight, and so on. But we all worry about whether the drive will unexpectedly die, since a truism going around is that SSD drives will just up-and-quit taking your whole computer with it. It's useful, therefore, to have fore-warning by monitoring the health of your SSD drive. A key is to ensure your drive has the S.M.A.R.T. feature (Self-Monitoring, Analysis and Reporting Technology). The next key is getting software that can query S.M.A.R.T. data, presenting it in a way that makes sense to you.

SSD drive lifetime expectancy explained

(March 26, 2017) SSD drives are awesome, they're extremely faster than spinning drives, lower weight, lower power consumption, no noise, and are a direct plug-in replacement for spinning drives. Thanks to technology advances the price is falling rapidly making them more feasible every day. The problem is they're known to suddenly die giving us a fear of losing our data and suddenly having to replace the drive. This video does an excellent job of explaining the reality, and tells us to not panic but instead to make sure to leave lots of free space on the drive.

Does a larger SSD drive have longer lifetime expectancy?

(November 19, 2017)

While SSD drives are awesome and give excellent performance, we all have a fear of the "Sudden SSD Death Syndrome" or that sudden "hey why did my computer just die" moment. While spinning-platter drives also wear out and die, the risk of SSD drive failure weighs in the back of our collective mind. A truism going around is that "overprovisioning" your SSD drive will ensure a longer lifespan for the drive.

How to build a large capacity, fast, portable SSD drive

(July 26, 2019) SSD drives are fast, light weight, very reliable, and require very little power. That makes them very attractive as portable drives when away from home. We might need more data storage than is in our laptop making an external portable drive a necessity. While we can buy a manufactured external SSD drive, it's also very easy to build our own.

SSD drive technology, MLC, TLC, SLC

(March 26, 2017) SSD drives are awesome, they're extremely faster than spinning drives, lower weight, lower power consumption, no noise, and are a direct plug-in replacement for spinning drives. Making the best choice between the available SSD's means understanding what MLC, TLC and SLC means. These acronyms cover different types of SSD drive, and tradeoff's between speed, performance, data storage and reliability. The 'C' in each acronym means 'Cell', and each refers to a different architecture.

DIY hard disk cages for DIY network attached storage (NAS)

(July 22, 2021) Looking at the prices and features of NAS devices like QNAP, Synology or Drobo, you might think it requires specialized parts at a high price. In reality, disk drives have standardized mounting holes, using standardized screws, and it's possible to build simple drive cages for a fraction of the price. To turn the do-it-yourself (DIY) drive cage into a data storage solution requires a couple more parts, such as a computer and some USB adapters. But the starting point is to build a low cost DIY drive cage.

How to buy a refurbished computer

(March 21, 2019) The system of selling us gadgets is geared to foist brand new gadgets on us. It can be expensive racing to keep up with the treadmill of upgrading to the latest thing every year, plus the environmental cost of throwing away perfectly good gadgets is enormous. Buying refurbished computers, cell phones or other gadgets, can save you a lot of money. It is much better for your budget and for the planet around us to ensure each gadget serves a long and useful life, rather than getting tossed away once a prettier gadget comes along. Since the game is designed with forced obsolescence in mind, those of us taking a different route have to tread carefully and decisively. This article is a guide to buying refurbished computers and other gear.

Upgrading or replacing battery pack, SSD and other parts on Acer C720 Chromebook's

(July 21, 2016) How many of us, if the trackpad on our laptop stops working, get frustrated, set the computer aside, and buy a new one? That costs money to replace the computer, more 'stuff' piles up, it disrupts our lives, but somehow it's easier to just replace than figure out how to fix it. Turns out this specific issue, the trackpad puzzlingly not working, could be easily fixed. In my case the battery pack had swollen pushing against the trackpad making it not work correctly. The swollen battery pack itself is very dangerous and I wouldn't have known of it otherwise. Further, the replacement was next to trivial and a lot cheaper and less disruptive than replacing the whole computer.

iFixit offers excellent value - repair kit plus excellent tools - iPhone 4S battery replacement

(May 13, 2019) I have an old iPhone 4S that I'm preparing to sell on eBay and one issue was that the battery had died. At iFixit a whole repair kit, battery plus tools, cost only $16 so I took the plunge to see about replacing the battery. I came away hugely impressed at the value, if only because the included tools are flat out excellent.

Displaying text on LCD screen from the Arduino UNO

(June 17, 2017)

The Arduino doesn't have an intrinsically native display. Programmers frequently debug their software by printing stuff to a screen, or they need a human-machine-interface to show what's happening, and even a simple text display can be quite handy.

With this article we'll install a particular kind of LCD display, and learn how to drive the LCD display using the LiquidCrystal library. This particular LCD requires wiring up a little circuit that uses a potentiometer to control brightness. While we might yearn for a simple-to-connect-display, we do learn a little electronics along the way. At the end of the day the Arduino is about encouraging us to fire up our soldering iron and making things.

Once you've wired the display, the LiquidCrystal library makes it easy to display text on the screen.

Arduino board and accessories buying guide.

(June 17, 2017)

The Arduino marketplace includes a long list of controller boards and add-on accessories. This guide shows some of the best Arduino-compatible products available.

Reliable data transmission with an Arduino

(July 5, 2018)

Communicating data is important - your Arduino might be used as a sensor, or to control some hardware, and therefore needs to either send data to another computer, or to receive commands from another computer. The core necessity is sending and receiving data. This video is an in-depth look at how to implement NRZ (Non-Return-To-Zero) data communications using a single pin on the Arduino. Also in the video is a look at connecting a certain LCD panel to an Arduino.

Using the Arduino serial console to monitor your Sketch

(July 6, 2017)

The most useful debugging tool many programmers have is the Print statement. They insert Print statements throughout their code, to see if the program got to certain points and if so what was the values. While there are fancy schmancy debugger packages available, the Print statement is extremely useful and simple. An Arduino presents a challenge because the software executes over on that teensy board, there's no computer display, no direct connection, where would the print statement send its output? Turns out the Arduino software stack includes a Serial console that you can view from inside the Arduino IDE. What we'll do in this article is go over a trivial example of reading an analog value to print on the serial console.

Build an FM radio using Arduino Nano and a TEA5767 Radio Module

(September 2, 2017)

With a few add-on parts, you can create your own customized FM radio receiver. The attached project uses an Arduino NANO and a TES5767 radio module that can be used either with Raspberry Pi or Arduino. The display is a Nokia 5110 LCD display, but you could use any display of your choosing. The TES5767 uses an I2C interface, making it easy to integrate, and making an I2C display unit a good addition.

Arduino UNO first step, connect to your laptop, run a simple application

(June 17, 2017)

The Arduino is an extremely popular microcontroller for open source DIY hardware hacking projects. There are many flavors of Arduino, and for this project we'll use an Arduino UNO. All Arduino's have a well-defined GPIO interface supporting "Shield" boards providing customized capabilities. The GPIO pins can be connected to your DIY hardware, or to 3rd party Shields, for which there are many suppliers. That's what makes the Arduino so interesting to regular folk like you and me. There's a whole slew of microcontroller chips and boards targeted to commercial and industrial systems. That's not who we are, we're hacking away in a spare bedroom.

With this article we'll take a first step or two to get an Arduino connected to our computer, get accustomed to the IDE, and upload a couple simple programs. Down at the bottom are a few videos.

Apple's unnecessarily complex SSD upgrade process for Mac Mini 2014/2015

(July 13, 2018)

The 2014/2015 Mac Mini is still, in 2018, the "current" Mac Mini model, and its biggest problem is the great difficulty to upgrade the device. While it is impossible to replace the memory it is possible to replace the hard drive, so long as you bought the upgradeable Mac Mini. Namely the version sold with an HDD. The other, with PCIe SSD, does not support upgrading the disk. You can save some money by purchasing the HDD version and upgrading to SSD on your own, however performance is higher with the PCIe version. The videos attached to this post document the overly unnecessarily difficult process for upgrading such Mac Mini's to have an SSD. You have to remove everything just to swap the disk? And you can't change the memory? The Intel NUC is in the same class of machine, and does not require this kind of over-the-top surgery.

Upgrade 2012 MacBook Pro to potentially equal later Retina MacBook Pros

(November 27, 2018)

Why spend megabucks for the latest Mac when you can save a lot by buying an older machine? With a few simple upgrades (maxing-out the memory, using SSD) an older machine can perform similarly to the latest models. I am typing this on a 2012 MacBook Pro with 16 GB memory and a 500GB SSD, plus a 750GB HDD, that is satisfying all my needs from writing articles to heavy-duty software development. Just because the manufacturer wants you to buy the latest, doesn't mean you must do so.

Initial evaluation of the cheapest 2010 MacBook Pro found on eBay in May 2019

(May 5, 2019) A couple weeks ago I bought a 15" 2010 MacBook Pro from eBay, the laptop was described as "for parts or repair", it didn't have a disk or battery, and cost only $75 (plus shipping). Does this sound like a good deal or a bad deal? A non-working older computer? What tipped me off it was a good risk is that the eBay listing showed the flashing disk icon, meaning the logic board was probably fine, and that the computer just needed a new disk drive.

Powering on the cheapest 2010 MacBook Pro found on eBay in 2019

(May 12, 2019) A couple weeks ago I bought a 15" 2010 MacBook Pro from eBay, the laptop was described as "for parts or repair", it didn't have a disk or battery, and cost only $75 (plus shipping). I am working on refurbishing this computer. In the previous segment, I performed an initial evaluation, installed a disk drive, started to install Mac OS X, the computer overheated, I found dust bunnies in the cooling system, then after cleaning that out the computer would not turn on. In this episode we will get it to turn on.

What does it cost to refurbish the cheapest 2010 MacBook Pro found on eBay in May 2019

(May 10, 2019) A couple weeks ago I bought a 15" 2010 MacBook Pro from eBay, the laptop was described as "for parts or repair", it didn't have a disk or battery, and cost only $75 (plus shipping). I am refurbishing the laptop, and am therefore paying for additional parts beyond the laptop. In this post I will list all the costs, and the income from selling it on eBay assuming I will sell it.

Replacing the keyboard on the cheapest 2010 MacBook Pro found on eBay in 2019

(May 12, 2019) A couple weeks ago I bought a 15" 2010 MacBook Pro from eBay, the laptop was described as "for parts or repair", it didn't have a disk or battery, and cost only $75 (plus shipping). I am working on refurbishing this computer. In this segment, I am replacing the keyboard. And while I'm at it, I fixed the placement of the trackpad.

Apple's big upgrade to the Mac Mini still isn't what it should be

(October 30, 2018)

Last week Apple unveiled a second round of updated machines, including the long-awaited update to the Mac Mini. While the upgrade is much appreciated, and one can easily upgrade memory, and it has a huge bump in processor capability, the 2018 Mac Mini simply is not what Apple needed to deliver. Intel's NUC is still far and away a better implementation of what the Mac Mini should be. Plus the Intel NUC is less than half the cost.

Apple 2009 Mac Pro back to the future for 2019 Modular Mac Pro, one hopes

(March 7, 2019)

Apple has promised the next Mac Pro, due during 2019, would be modular without explaining what they mean. As I've been documenting on TechSparx, Apple's current design style is unrepairable unmodifiable machines. The sort of Pro users who would want a Mac Pro, however, want upgradeability for example to swap in new graphics cards or max out the memory. In short, the design ethos Apple should follow is precisely the 2009/2010 Mac Pro design.

What is the T2 Security Chip on modern MacBook's

(August 1, 2019) At some point Apple designed the MacBook's and MacBook Pros with the T2 Security Chip. It's just there, and supposedly it's a good idea. But like all things, it's useful to know what the chip does, and more importantly why Apple designed this chip into the system. Supposedly it increases security, otherwise why is it called the Security Chip, but is there another purpose. Apple is famously tight-lipped about its roadmap, so what if this is a game of multi-dimensional chess where the T2 chip is a harbinger of something else?

How to upgrade a cheap (like, $100) MacBook Pro to modern standards in 2019

(April 10, 2019) Buying an older computer might seem stupid, but you can save a lot of money, and have that warm fuzzy feeling inside of helping the planet. An "old" (2009?) computer in 2019 might seem a rubbish idea, but there are two simple upgrades that are a cheap and easy to give that old computer a new lease on life. For most of us the older computers are still powerful enough, especially with upgraded parts inside. If you really and truly need high end graphics -- like you're editing video all the time -- skip this posting, because it's not for you. But most of us are just browsing the web and writing documents, and will be perfectly served by an old computer at a fraction of the cost. For this posting I'll look at a couple eBay postings for the cheapest MacBook Pro's and evaluate what kind of upgrade can be done.

Installing macOS High Sierra on a Windows disk and Disk Utility says 'Couldn't modify partition map'

(June 7, 2019) I have installed Mac OS X dozens of times, including a couple dozen times installing it onto a bare drive. You boot the OS X installer thumb drive, then run Disk Utility to format the disk, return to the installer, and have at it. But in this case Disk Utility refused to format the disk saying it "Couldn't modify partition map". The key data point is the disk in question had come from a Windows computer.

Installing macOS High Sierra on a MacBook Pro or other Mac that is not supported by High Sierra

(April 12, 2018)

Apple has declared certain older Mac computers unsupported by newer versions of macOS. In my case, I attempted to install macOS High Sierra on a mid-2009 MacBook Pro, but the installer failed in a very strange way. I constructed a USB installer using the normal process to make a macOS installer, then rebooted the computer to run the installation, but instead the screen simply went blank and the computer turned itself off. In other words installing macOS High Sierra on this mid-2009 MacBook Pro failed in a strange way. After a couple dozen macOS installs on different computers under my belt, I'd never seen this behavior. After some duckduckgoing the cause was found to be this screen capture - that the computer was not supported by High Sierra - and fortunately there was a relatively simple solution.

Installing MacOSX when the installer says: OS X could not be installed on your computer. No packages were eligible for install.

(2016-10-16 15:41)

A key step for upgrading the disk on a MacBook Pro is to install a new operating system on the new drive, and then use Migration Assistant to copy over the old data. Depending on how you went about the work, installing Mac OS X on the new system may give you a message: OS X could not be installed on your computer. No packages were eligible for install.

This is what it looks like in the installer. Upon seeing this I went "HUH?" because the installation was from a thumb drive I'd used many times to install Mac OS X (El Capitan) successfully.

Apple lied about 2018 Mac Mini upgradeability

(November 8, 2018)

In October, Apple finally released the upgraded Mac Mini and one leading feature is that we can again upgrade the memory. That we cannot upgrade the storage is sad, but at least we can upgrade the memory. However the picture Apple showed - that we can easily get in and change the memory - is a lie. The innards (once you open the case) look nothing like this, and upgrading the memory requires a near-complete disassembly.

2018 Apple Mac Mini Pro cannot run/boot Linux

(November 6, 2018)

Many of us like Apple's hardware but not the operating system, and prefer to run Linux or even Windows. Yeah, it's a little crazy to pay a premium price for the hardware just to run some other operating system, that's how good Apple's hardware is. It's been discovered the 2018 Mac Mini has hardware to prohibit booting unapproved operating systems.

Apple's Mac Mini Pro: What it should be

(April 8, 2018)

As a former Mac Mini owner, and a happy Intel NUC owner, I have one suggestion to Apple regarding the Mac Mini. Make it more like the Intel NUC. Apple should be completely embarrassed that Intel has made a better Mac Mini than the Mac Mini. If Intel can do it to perfection, Apple should be able to do it. But with the direction Apple is taking with its hardware design, an updated Mac Mini is going to be even more locked down than that abomination of a Mac Mini Apple released in 2014.

Apple 2018 Mac Mini reviews

(November 12, 2018)

In October, Apple finally released the upgraded Mac Mini and early reviews suggest it is a powerhouse. Computationally, that is, thanks to a 6 core Core i7 CPU, but graphics-wise it isn't so hot. While the graphics chip is perfectly usable for every day use, it isn't enough for those with high-end graphics needs such as videographers. But, the port selection on the back of the 2018 Mac Mini means you can integrate an external GPU (eGPU) unit to drive high-end graphics cards.

The list of parts to build your own iPhone 7

(July 11, 2018)

Scotty of Strange Parts has published several in-depth videos on building an iPhone, and building custom iPhones including adding a headphone jack to an iPhone 7. In this video he walks us through the parts required to build an iPhone from parts. This is not just the logic board, screen, battery, and case, but all the parts, as well as hints on which parts to be extra careful aboutl

How to add a headphone jack to iPhone 7

(September 7, 2017)

Apple really screwed up the iPhone design with the iPhone 7 by not putting in a headphone jack. I don't care about their prescriptive ideas about this, we need a headphone jack dammit. This video is from the guy who built his own iPhone from spare parts he bought in Shenzen China. For this video, he'd bought an iPhone 7 in order to record better videos and found himself really wanting a headphone jack. So, he decided to launch into adding such a jack, knowing there are millions of others around the world chafing at Apple's preconcieved notions and wanting a headphone jack on their iPhone 7.

The process took 17 weeks of trial and error. He started with noting there's an empty space where the headphone jack belongs, and that it'd be vaguely possible to add hardware into that space. What took the 17 weeks is designing a custom circuit, on a flexible substrate, learning to solder flexible circuits and work under a microscope, and to learn how to assemble the result without breaking the parts. That last bit was expensive due to the large number of expensive parts he broke. But, he came out the end with success and a vow to release the design files to the public via his website, and a strong plea to Apple to add a dang headphone jack to the iPhone 8.

How to add internal wireless charging to an iPhone 7

(August 24, 2018)

Apple does not make an iPhone with internal wireless charging support. Scotty of Strange Parts found a guy in China who developed a kit to add wireless charging capability inside an iPhone 7. It is a slim circuit including Wireless Charging antenna and a connector which slips into an iPhone 7 connector. It requires replacing the back, so there is a port-hole through which wireless charging signals can get into the phone.

The video attached here is a fascinating look at not only getting into an iPhone 7 and making modifications, but the hardware development environment in the Chinese electronics markets. We get to see Scotty taking apart and reassembling an iPhone 7 several times, testing and debugging, and finally getting the thing to work. Plus, we get to see Scotty negotiating with Chinese hardware developers.

The big result is that Scotty is making available kits at

In China you can build your own iPhone from spare parts

(Apr 12, 2017) This American entrepreneur goes to Shenzen China frequently. As he observed the scene over several months, it came to mind the electronics shops carry enough spare parts one could assemble their own iPhone. From spare parts, plus specific shop workers with the specialized skills for correct assembly. The big time-saver is to buy a working logic board, rather than soldering components onto an unpopulated logic board. But, with perseverance, and the willingness to traverse chaotic crowded markets, the parts are not only available, but it's possible to find iPhone-compatible backs with designs Apple never thought of. The video takes us on the journey, showing us the insides of not only the Shenzen markets but some snippets of electronics disassembly/recycling operations.

Steve Wozniak Debunks One of Apple's Biggest Myths

(December 3, 2014) Steve Wozniak takes us on a walk down history lane, retelling how much he loves designing computer hardware, and that he designed the Apple 1 for fun. Then Steve Jobs came along, and turned that hobby into a big business, making several people into multijillionaires. Wozniak says he just wanted to be an engineer at the bottom of the Org Chart, and left Apple in 1987.

Theory/plan to avoid overheating Apple Airport Time Capsule A1254/A1302/A1355/A1409

(February 20, 2020) The Apple Airport Time Capsule product line is an excellent and sleek way to keep Mac's backed up, and they can also function as a very nice NAS. The box is small and indiscreet, able to be tucked out of the way somewhere, but it can be attached to ones WiFi router where it automates keeping your computer backed up. It can even serve double duty as ones WiFi router, and interoperate with other Airport products to implement a house-spanning WiFi system that's easy to administer. But it seems they run a bit hot, and I'm worried about hard disk longevity in the hot environment inside the box.

The reason we cannot access a Time Capsule drive from Windows is stupid

(February 28, 2020) The Apple Airport Time Capsule product line is an excellent and sleek sort of NAS device that also has excellent support for Apple's Time Machine. It works really well with Apple Mac's, with great out of the box features. I assumed it would also work as well for a Windows PC, and got one for my girlfriend for her use. But it turns out that Windows machines cannot access Time Capsule drives, unless you enable an extremely dangerous piece of software.

Apple Airport Time Capsule A1254/A1302/A1355/A1409 teardown

(February 20, 2020) The Apple Airport Time Capsule product line is an excellent and sleek way to keep Mac's backed up, and they can also function as a very nice NAS. This article shows a teardown of the A1254 first generation Time Capsule. Since the A1302, A1355 and A1409 use the same design, the teardown is appropriate for them as well. It should also apply to the Apple Airport Express models like the A1408 that have a similar design.