CCA Ethernet Cables: Not Up To Scratch, But Are They Dangerous?

April 7, 2026 by Lewin Day 54 Comments

If you’ve ever bought a suspiciously cheap Ethernet cable from an online listing, there’s a decent chance you’ve encountered Copper Clad Aluminum. Better known as CCA, it’s exactly what it sounds like—an aluminium conductor with a thin skin of copper deposited on the outside. Externally, cables made with this material look largely like any other, with perhaps the only obvious tell being that they feel somewhat lighter in the hand.

CCA is cheaper than proper copper cabling, and it conducts signals well enough to function in an Ethernet cable. And yet, it’s a prime example of corner-cutting that keeps standards bodies and professional installers up at night. But just how dangerous is this silent scourge, found lurking in so many network cabinets around the world?

Not Up To Scratch

CCA wire is typically made by wrapping an aluminium core with copper strip and then extruding it through a die. Credit: USPTO

Everything you need to know about CCA is in the name—it refers to an aluminium wire with a thin copper cladding, typically applied through a die extrusion process. The reasoning behind this exploits a real physical phenomenon called the skin effect, wherein higher-frequency AC signals tend to travel along the outer surface of a conductor. The idea goes that since most of the current moves through the outer copper skin layer anyway, the less-conductive aluminium core doesn’t unduly impact the wire’s performance. Using copper-clad aluminium wiring is, in theory, desirable because aluminium is much cheaper than copper, which can really add up over long cable runs. Imagine you’re wiring a building with with hundreds of miles of Ethernet cabling, all with eight conductors each—the savings add up pretty quickly.

There’s a problem with CCA cabling in these contexts, though. Due to prevailing cabling standards, any cable made with CCA is technically not even a real Ethernet cable at all. The relevant documents are unambiguous.

ANSI/TIA-568.2-D requires conductors in Category-rated cable to be solid or stranded copper. No other materials are acceptable, and thus CCA is explicitly excluded from use in Category cable applications. A cable with CCA conductors cannot legitimately carry a Cat5e, Cat6, or any related designation under any circumstances. Similarly, ISO/IEC 11801 has the same requirement. The U.S. National Electrical Code also states that conductors in communications cables, other than coaxial cable, shall be copper. This isn’t a suggestion or a best practice; it’s the letter of the code. Anything lesser is simply not allowed. Continue reading “CCA Ethernet Cables: Not Up To Scratch, But Are They Dangerous?” →

Sega Meganet: Online Gaming In 1990

April 2, 2026 by Lewin Day 20 Comments

It’s easy to think of online console gaming as an invention of the 2000s. Microsoft made waves when Xbox Live dropped in 2002, with Nintendo and Sony scrambling to catch up with their own offerings that were neither as sleek or well-integrated.

However, if you were around a decade earlier, you might have experienced online console gaming much closer to the dawn of the Internet era. As far back as 1990, you could jump online with your Sega Mega Drive. But what did an online console feel like in the dial-up era?

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Solar Balconies Take Europe By Storm

March 31, 2026 by Lewin Day 143 Comments

Solar power has been around for a long time now. Once upon a time, it was mostly the preserve of research projects and large-scale municipal installations. Eventually, as the technology grew ever cheaper, rooftop solar came along, and cashed-up homeowners rushed to throw panels on their homes to slash their power bills and even make money in some cases.

Those in apartments or rented accommodations had largely been left out of the solar revolution. That was, until the advent of balcony solar. Popular in Germany, but little known in the rest of the world, the concept has brought home power generation to a larger market than ever.

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This Flow Battery Operates With No Pump Required

March 27, 2026 by Lewin Day 6 Comments

Flow batteries are rather unique. They generate electricity by the combination of two fluids flowing on either side of a membrane. Typically, this involves the use of some kind of pump to get everything moving. However, [Dusan Caf] has demonstrated another way to make a flow battery operate.

[Dusan]’s build is a zinc-iodide flow battery. It uses two 3D printed reservoirs, each holding a ZnI₂ solution and a graphite electrode. Unlike traditional flow batteries, there is no mechanism included to mechanically push the fluid around. Instead, fluid motion is generated by the magnetohydrodynamic effect, which you may know from that Japanese boat that didn’t work very well.

When charging the liquid-based cell, current flows through the conductive electrolyte that sits between both electrodes. This sees zinc electroplated onto the graphite anode, while iodide ions are oxidized at the cathode. There’s also a permanent magnet installed beneath the electrodes, which provides a stable magnetic field. This field, combined with the current flowing through the electrolyte, sees the Lorentz force pushing the electrolyte along, allowing the flow battery to operate. When the cell is being discharged, the reactions happen in reverse, with the flow through the electrodes changing direction in turn. Neatly, as current draw or supply increases, the flow rate increases in turn, naturally regulating the system.

[Dusan] notes this isn’t feasible for large batteries, due to the limited flow rate, but it’s fine for small-scale demos regarding the operation of a flow battery. We’ve featured some more typical flow battery designs in the past, too.

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Momentus Clock Aims To Find Meaning

March 26, 2026 by Lewin Day 8 Comments

A lot of the time, we must assign our own meaning to the numbers on the clock. 8:30 AM is work kicking off, 12 PM is lunch, and 5PM is when the corporate chains release us to what’s left of the day. If you’d rather the clock tell you what’s special about the current time, though, you might like this project from [Andy Isaacson].

It’s called Momentous—”a clock to make every minute meaningful” in [Andy’s] own words. The concept is simple—for each minute, the clock digs up some random mathematical fact relevant to the current time. For example, you might think of 3:14 as Pi o’clock, but Momentous also notes that the sequence “314” shows up at the 856th decimal of e. Useful? Probably not. Fun? If you like numbers, then very!

[Andy] wrote Momentous in Typescript with React Native and Expo. Baked into the app is a computed list of fun number facts for every conceivable time from 00:00 to 23:59. All these timely numbers were processed through a “fact generation” algorithm to dig up mathly tidbits. Do they contain primes? Do the numbers show up in a famous irrational number sequence? Are they palindromic, or can some neat facts be gleaned from Wikipedia? Maybe the current time shows up in your best friend’s phone number! Momentous uses all these and more to make every minute of the day a little bit more interesting.

You can check out the clock for yourself in your web browser. Alternatively, you can install it on your iPhone if you so desire. We feature all kinds of fun clocks here, from the wordy to the absurdy. If you’re cooking up your own timely hacks, we always love to to hear about them on the tipsline!

3D Print Becomes Cast Iron Wrench Via Microwave

March 26, 2026 by Lewin Day 36 Comments

Consumer-grade 3D printing is good for prototyping and making relatively soft plastic stuff. If you wanna make tough things, though, it’s really hard to beat the strength of metal. [Shake the Future] has produced a guide on using 3D printing in a process to produce solid parts out of actual cast iron.

The concept is simple. [Shake the Future] uses silicon carbide crucibles, which can heat up by absorbing microwave energy. Put one in an insulated container, dump some metal in, and throw it in a microwave, and soon enough you have a pot of molten metal you can use to cast stuff.

Let’s say you want to make an adjustable wrench, which is how [Shake the Future] demonstrates this technique. The first step is to print the wrench parts in plastic, such as PLA. These parts are then packed into fine sand to create casting molds. The PLA is burned out of the mold, leaving a negative imprint of the geometry. Molten cast iron can then be poured into the mold to create the part in solid metal.

It’s a messy technique that requires a lot of manual labor, but it does work quite well. There are some tricks to learn, though, particularly when it comes to successfully casting parts with holes or fine geometric features.

And before you think that you’re going to put the hardware store out of business, it should also be noted that it failed on first encounter with a real-world nut. The thinnest part by the screw just wasn’t strong enough.

Still, it’s a great demo, and if you’ve ever wanted to make a bespoke cast iron part of your own, this work may be very relevant to you. Alternatively, consider learning about DIY aluminium casting—just consider the pitfalls involved.

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VGA Output From A PIC18

March 25, 2026 by Lewin Day 6 Comments

In the maker world, it’s the Arduino and ESP32 lines that get the lion’s share of attention. However, you can do fantastic things with PIC chips, too, if you put the dev time in—it’s just perhaps less likely another maker has done so before you. A great example is this VGA output project from [grecotron].

A PIC18F47K42 is perhaps not the first part you would reach for to pursue any sort of video-based project. However, with the right techniques, you can get the 8-bit microcontroller pumping out the pixels surprisingly well. [grecotron] was able to get the chip outputting to a VGA monitor at a resolution of 360 x 480 with up to 16 colors. It took some careful coding to ensure the chip could reliably meet the timing requirements for the standard and to get HSYNC, VSYNC, and the color signals all dancing in harmony. Aiding in this regard was that the chip was clocked with a 14.3182 MHz crystal to make it easy to divide down from all the internal timers as needed. Supporting hardware is light, too—primarily consisting of a VGA connector, a couple of multiplexers, and resistor ladder DACs for the color signals. Files are on Github for those interested in deeper detail on the work.

VGA output is possible to implement on all kinds of microcontrollers—and even a bunch of raw logic if you know what you’re doing. If you’re pursuing your own video output wizardry, be sure to let us know on the tipsline.