Lessons Learned After A Head-First Dive Into Hardware Manufacturing

February 9, 2026 by Maya Posch 10 Comments

Sometimes you just know that you have the best ever idea for a hardware product, to the point that you’re willing to quit your job and make said product a reality. If only you can get the product and its brilliance to people, it would really brighten up their lives. This was the starry-eyed vision that [Simon Berens] started out with in January of 2025, when he set up a Kickstarter campaign for the World’s Brightest Lamp.

At 50,000 lumens this LED-based lamp would indeed bring the Sun into one’s home, and crowdfunding money poured in, leaving [Simon] scrambling to get the first five-hundred units manufactured. Since it was ‘just a lamp’, how hard could it possibly be? As it turns out, ‘design for manufacturing’ isn’t just a catchy phrase, but the harsh reality of where countless well-intended designs go to die.

The first scramble was to raise the lumens output from the prototype’s 39K to a slight overshot at 60K, after which a Chinese manufacturer was handed the design files. This manufacturer had to create among other things the die casting molds for the heatsinks before production could even commence. Along with the horror show of massive US import taxes suddenly appearing in April, [Simon] noticed during his visit to the Chinese factory that due to miscommunication the heatsink was completely wrong.

Months of communication and repeated trips to the factory follow after this, but then the first units ship out, only for users to start reporting issues with the control knobs ‘scraping’. This was due to an issue with tolerances not being marked in the CNC drawings. Fortunately the factory was able to rework this issue within a few days, only for users to then report issues with the internal cable length, also due to this not having been specified explicitly.

All of these issues are very common in manufacturing, and as [Simon] learned the hard way, it’s crucial to do as much planning and communication with the manufacturer and suppliers beforehand. It’s also crucial to specify every single part of the design, down to the last millimeter of length, thickness, diameter, tolerance and powder coating layers, along with colors, materials, etc. ad nauseam. It’s hard to add too many details to design files, but very easy to specify too little.

Ultimately a lot of things did go right for [Simon], making it a successful crowdfunding campaign, but there were absolutely many things that could have saved him a lot of time, effort, lost sleep, and general stress.

Thanks to [Nevyn] for the tip.

The function generator circuit on a breadboard

555-Based Square-Wave And Triangle-Wave Function Generator Build For Beginners

February 7, 2026 by John Elliot V 7 Comments

Over on YouTube [Andrew Neal] has a Function Generator Build for Beginners.

As beginner videos go this one is fairly comprehensive. [Andrew] shows us how to build a square-wave generator on a breadboard using a 555 timer, explaining how its internal flip-flop is controlled by added resistance and capacitance to become a relaxation oscillator. He shows how to couple a potentiometer to vary the frequency.

He then adds an integrator built from a TL082 dual op amp to convert the circuit to a triangle-wave generator, using its second op amp to build a binary inverter. He notes that a binary inverter is usually implemented with a comparator, but he uses the op amp because it was spare and could be put to good use. Again, potentiometers are added for frequency control, in this case a 1 MΩ pot for coarse control and a 10 kΩ pot for fine control. He ends with a challenge to the viewer: how can this circuit be modified to be a sine-wave generator? Sound off in the comments if you have some ideas!

If you’re interested to know more about function generators check out A Function Generator From The Past and Budget Brilliance: DHO800 Function Generator.

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A graph of current versus time for circuits with and without inductors

A Deep Dive Into Inductors

February 5, 2026 by John Elliot V 5 Comments

[Prof MAD] runs us through The Hidden Power of Inductors — Why Coils Resist Change.

The less often used of the passive components, the humble and mysterious inductor is the subject of this video. The essence of inductance is a conductor’s tendency to resist changes in current. When the current is steady it is invisible, but when current changes an inductor pushes back. The good old waterwheel analogy is given to explain what an inductor’s effect is like.

There are three things to notice about the effect of an inductor: increases in current are delayed, decreases in current are delayed, and when there is no change in current there is no noticeable effect. The inductor doesn’t resist current flow, but it does resist changes in current flow. This resistive effect only occurs when current is changing, and it is known as “inductive reactance”.

After explaining an inductor’s behavior the video digs into how a typical inductor coil actually achieves this. The basic idea is that the inductor stores energy in a magnetic field, and it takes some time to charge up or discharge this field, accounting for the delay in current that is seen.

There’s a warning about high voltages which can be seen when power to an inductor is suddenly cut off. Typically a circuit will include snubber circuits or flyback diodes to help manage such effects which can otherwise damage components or lead to electric shock.

[Prof MAD] spends the rest of the video with some math that explains how voltage across an inductor is proportional to the rate of change of current over time (the first derivative of current against time). The inductance can then be defined as a constant of proportionality (L). This is the voltage that appears across a coil when current changes by 1 ampere per second, opposing the change. The unit is the volt-second-per-ampere (VsA^-1) which is known as the Henry, named in honor of the American physicist Joseph Henry.

Inductance can sometimes be put to good use in circuits, but just as often it is unwanted parasitic induction whose effects need to be mitigated, for more info see: Inductance In PCB Layout: The Good, The Bad, And The Fugly.

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Toybox Tractor: Plywood, Lathe Hacks, And 350W Of Fun

February 5, 2026 by Matt Varian 13 Comments

When you think of a toy tractor, what probably comes to mind is something with fairly simple lines, maybe the iconic yellow and green, big rear tires, small front ones. Well, that’s exactly what [James] built, with simple, clean lines and a sturdy build that will hold up to driving around off-road in the garden. This Tractor is a great build, combining CAD, metal and wood work, some 3D printing, and electronics.

Starting at the power plant for the build, [James] went with a 350W DC motor powered by a 36V Li-ion battery from an e-bike. The motor turns a solid rear axle he made on a mini-lathe, connected to a set of riding lawn mower wheels. The mini-lathe spindle bore was too small to accommodate the shaft, and the lathe was not long enough to use the tailstock, so [James] had to get creative, using a vice and a piece of wood to make a stand–in tailstock, allowing him to turn this custom rear axle. The signature smoothly curved bonnet was made possible with plywood and body filler, rather than the sheet metal found on full-sized tractors. In fact, most of the build’s frame used plywood, giving it plenty of strength and, once painted, helping give it the appearance of a toy pulled out of a toybox.

This build had a bit of many domains in it, and all combined into a fantastic final result that no doubt will bring a smile to any face that gets to take the Tractor for a ride. Thanks [James] for documenting your build process, the hacks needed to pull off the tough bits along the way in making this fun toy. If you found this fun, be sure to check out another tractor related project.

Simulating Pots With LTSpice

January 21, 2026 by Al Williams 9 Comments

One of the good things about simulating circuits is that you can easily change component values trivially. In the real world, you might use a potentiometer or a pot to provide an adjustable value. However, as [Ralph] discovered, there’s no pot component in LTSpice. At first, he cobbled up a fake pot with two resistors, one representing the top terminal to the wiper, and the other one representing the wiper to the bottom terminal. Check it out in the video below.

At first, [Ralph] just set values for the two halves manually, making sure not to set either resistor to zero so as not to merge the nets. However, as you might guess, you can make the values parameters and then step them. Continue reading “Simulating Pots With LTSpice” →

TV Remote Uses Floppy Disks

January 19, 2026 by Bryan Cockfield 9 Comments

Famously, the save icon on most computer user interfaces references a fairly obsolete piece of technology: the venerable floppy disk. It’s likely that most people below the age of about 30 have never interacted with one of these once-ubiquitous storage devices, so much so that many don’t recognize the object within the save icon itself anymore. [Mads Chr. Olesen]’s kids might be an exception here, though, as he’s built a remote control for them that uses real floppy disks to select the programming on the TV.

This project partially began as a way to keep the children from turning into zombies as a result of the modern auto-play brainrot-based economies common in modern media. He wanted his kids to be able to make meaningful choices and then not get sucked into these types of systems. The floppy disk presents a perfect solution here. They’re tangible media and can actually store data, so he got to work interfacing a real floppy disk drive with a microcontroller. When a disk is inserted the microcontroller wakes up, reads the data, and then sends out a command to stream the relevant media to the Chromecast on the TV. When the disk is removed, the microcontroller stops play.

Like any remote, this one is battery powered as well, but running a microcontroller and floppy disk drive came with a few challenges. This one is powered by 18650 lithium cells to help with current peaks from the drive, and after working out a few kinks it works perfectly for [Mads] children. We’ve seen a few other floppy disk-based remote controls like this one which replaces the data stored on the magnetic disc with an RFID tag instead.

A hand holding the Zoyi ZT-QB9 Smart Clamp meter

Review And Demo Of The Zoyi ZT-QB9 Smart Clamp Meter

January 18, 2026 by John Elliot V 14 Comments

Over on YouTube [Kiss Analog] reviews the New Zoyi ZT-QB9 Smart Clamp meter.

If you’re putting together an electronics lab from scratch you absolutely must get a multimeter to start. A typical multimeter will be able to do current measurements but it will require you to break the circuit you’re measuring and interface it to your meter using its mechanical probes.

A good choice for your second, or third, multimeter is a clamp-based one. Many of the clamp meters have the clamp probe available for current measurements while still allowing you to use the standard 4mm banana jack probes for other measurements, particularly voltage and resistance.

If you’re curious to know more about how clamp meters work the answer is that they rely on some physics called the Hall Effect, as explained by the good people at Fluke.

In the video the following clamp meters are seen: Zoyi ZT-QB9, PROVA 11, and Hioki CM4375. If you’re in the market for a clamp meter you might also like to consider the EEVblog BM036 or a clamp meter from Fluke.

We have of course posted about clamp meters before. Check out Frnisi DMC-100: A Clamp Meter Worth Cracking Open or ESP32 Powers DIY Smart Energy Meter if you’d like to know more. Have your own trusty clamp meter? Don’t need no stinkin’ clamp meter? Let us know in the comments!

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