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Here Comes the Keurig of Everything

Startups introduce the Keurig of cocktails, the Keurig of Jell-O shots, and the Keurig of dinner. Let’s retire this metaphor before we get a “Keurig for Cats”

2 min read
Here Comes the Keurig of Everything
Photo: Tekla Perry

Keurig. It’s not the only single-serve coffee maker, but its name has become synonymous with single-serve beverage-making device. It’s been criticized by environmentalists, but Keurig’s dominance grows—every time I walk down the coffee aisle of my local grocery store I see more shelf space dedicated to K-cups (the Keurig pod) and less to traditional coffee and tea.

So it’s no surprise that entrepreneurs look at Keurig’s success and think, “Hey, I could make a smart machine that’s a Keurig for (insert your favorite consumable here).”

This week, I went to two startup launch events: HAX, formerly Haxlr8r, a hardware accelerator based in Shenzhen, China, and San Francisco; and MakerCon’s Launch Pad startup competition, held in San Francisco. And there was a Keurig-for-something at each.

At HAX, Bartesian introduced a Keurig for cocktails, in particular, drinks made with vodka, gin, rum, or tequila. The gadget has four tanks—one for each spirit—and disposable single-drink capsules containing concentrated, shelf stable juices, syrups, sugars, bitters, and other mixers. They’re starting with six “flavors,” three familiar drinks—Sex on the Beach, the Classic Cosmo, and the Margarita—and three of their own blends. The concept is limited—I don’t see how they could add a carbonated mixer, for example.

I sampled the margarita, and I have to say I was disappointed. The drink was horrid; the founders told me that’s because they used cheap tequila. Hint to startups—if you’re trying to show off the skills of a robot bartender, spring for a top shelf brand. Pricing wasn’t announced, but company founders indicated it would be around the cost of a Keurig, which puts it under $200. Bartesian will be launching on Kickstarter in a month.

But Bartesian is not the first startup out of the Keurig-for-cocktails gate. Somabar’s version already raised $312,000 on Kickstarter. It isn’t fully Keurig’d (it uses refillable tanks instead of plastic pods) but the on-demand result is similar. Meanwhile, Jevo aims to be the Keurig of Jell-O shots, and Synek aims to be the Keurig of beer. And for folks who would rather grow their intoxicant than mix it, there’s Root, an automated home gardening system that some have called a Keurig for marijuana.


At MakerCon’s Launch Pad, Sereneti Kitchen introduced a device called Cookie; it’s a Keurig for food, designed to make stir fries, stews, risottos—any dish with a relatively small list of ingredients that can be made in a single pot. The company plans to roll out a subscription plan, offering trays of fresh, local, and pre-cut ingredients with downloadable recipes. Cookie, the robot chef, dispenses the ingredients at appropriate times, adjusts the cooking temperature, and stirs. Sereneti plans to launch its crowd funding campaign early next year.

I just don’t see it. Stirring really is not the hard part of cooking, except, perhaps, for a risotto, and risottos aren’t consumed quite as often as coffee.

If these two types of gadgets don’t catch on, perhaps the lesson learned will be that we don’t actually need a Keurig for everything. If they turn out to be big hits, well, I might be looking for a little angel money to develop a “Keurig for Cats.”

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The Inner Beauty of Basic Electronics

Open Circuits showcases the surprising complexity of passive components

5 min read
A photo of a high-stability film resistor with the letters "MIS" in yellow.
All photos by Eric Schlaepfer & Windell H. Oskay

Eric Schlaepfer was trying to fix a broken piece of test equipment when he came across the cause of the problem—a troubled tantalum capacitor. The component had somehow shorted out, and he wanted to know why. So he polished it down for a look inside. He never found the source of the short, but he and his collaborator, Windell H. Oskay, discovered something even better: a breathtaking hidden world inside electronics. What followed were hours and hours of polishing, cleaning, and photography that resulted in Open Circuits: The Inner Beauty of Electronic Components (No Starch Press, 2022), an excerpt of which follows. As the authors write, everything about these components is deliberately designed to meet specific technical needs, but that design leads to “accidental beauty: the emergent aesthetics of things you were never expected to see.”

From a book that spans the wide world of electronics, what we at IEEE Spectrum found surprisingly compelling were the insides of things we don’t spend much time thinking about, passive components. Transistors, LEDs, and other semiconductors may be where the action is, but the simple physics of resistors, capacitors, and inductors have their own sort of splendor.

High-Stability Film Resistor

A photo of a high-stability film resistor with the letters "MIS" in yellow.

All photos by Eric Schlaepfer & Windell H. Oskay

This high-stability film resistor, about 4 millimeters in diameter, is made in much the same way as its inexpensive carbon-film cousin, but with exacting precision. A ceramic rod is coated with a fine layer of resistive film (thin metal, metal oxide, or carbon) and then a perfectly uniform helical groove is machined into the film.

Instead of coating the resistor with an epoxy, it’s hermetically sealed in a lustrous little glass envelope. This makes the resistor more robust, ideal for specialized cases such as precision reference instrumentation, where long-term stability of the resistor is critical. The glass envelope provides better isolation against moisture and other environmental changes than standard coatings like epoxy.

15-Turn Trimmer Potentiometer

A photo of a blue chip
A photo of a blue chip on a circuit board.

It takes 15 rotations of an adjustment screw to move a 15-turn trimmer potentiometer from one end of its resistive range to the other. Circuits that need to be adjusted with fine resolution control use this type of trimmer pot instead of the single-turn variety.

The resistive element in this trimmer is a strip of cermet—a composite of ceramic and metal—silk-screened on a white ceramic substrate. Screen-printed metal links each end of the strip to the connecting wires. It’s a flattened, linear version of the horseshoe-shaped resistive element in single-turn trimmers.

Turning the adjustment screw moves a plastic slider along a track. The wiper is a spring finger, a spring-loaded metal contact, attached to the slider. It makes contact between a metal strip and the selected point on the strip of resistive film.

Ceramic Disc Capacitor

A cutaway of a Ceramic Disc Capacitor
A photo of a Ceramic Disc Capacitor

Capacitors are fundamental electronic components that store energy in the form of static electricity. They’re used in countless ways, including for bulk energy storage, to smooth out electronic signals, and as computer memory cells. The simplest capacitor consists of two parallel metal plates with a gap between them, but capacitors can take many forms so long as there are two conductive surfaces, called electrodes, separated by an insulator.

A ceramic disc capacitor is a low-cost capacitor that is frequently found in appliances and toys. Its insulator is a ceramic disc, and its two parallel plates are extremely thin metal coatings that are evaporated or sputtered onto the disc’s outer surfaces. Connecting wires are attached using solder, and the whole assembly is dipped into a porous coating material that dries hard and protects the capacitor from damage.

Film Capacitor

An image of a cut away of a capacitor
A photo of a green capacitor.

Film capacitors are frequently found in high-quality audio equipment, such as headphone amplifiers, record players, graphic equalizers, and radio tuners. Their key feature is that the dielectric material is a plastic film, such as polyester or polypropylene.

The metal electrodes of this film capacitor are vacuum-deposited on the surfaces of long strips of plastic film. After the leads are attached, the films are rolled up and dipped into an epoxy that binds the assembly together. Then the completed assembly is dipped in a tough outer coating and marked with its value.

Other types of film capacitors are made by stacking flat layers of metallized plastic film, rather than rolling up layers of film.

Dipped Tantalum Capacitor

A photo of a cutaway of a Dipped Tantalum Capacitor

At the core of this capacitor is a porous pellet of tantalum metal. The pellet is made from tantalum powder and sintered, or compressed at a high temperature, into a dense, spongelike solid.

Just like a kitchen sponge, the resulting pellet has a high surface area per unit volume. The pellet is then anodized, creating an insulating oxide layer with an equally high surface area. This process packs a lot of capacitance into a compact device, using spongelike geometry rather than the stacked or rolled layers that most other capacitors use.

The device’s positive terminal, or anode, is connected directly to the tantalum metal. The negative terminal, or cathode, is formed by a thin layer of conductive manganese dioxide coating the pellet.

Axial Inductor

An image of a cutaway of a Axial Inductor
A photo of a collection of cut wires

Inductors are fundamental electronic components that store energy in the form of a magnetic field. They’re used, for example, in some types of power supplies to convert between voltages by alternately storing and releasing energy. This energy-efficient design helps maximize the battery life of cellphones and other portable electronics.

Inductors typically consist of a coil of insulated wire wrapped around a core of magnetic material like iron or ferrite, a ceramic filled with iron oxide. Current flowing around the core produces a magnetic field that acts as a sort of flywheel for current, smoothing out changes in the current as it flows through the inductor.

This axial inductor has a number of turns of varnished copper wire wrapped around a ferrite form and soldered to copper leads on its two ends. It has several layers of protection: a clear varnish over the windings, a light-green coating around the solder joints, and a striking green outer coating to protect the whole component and provide a surface for the colorful stripes that indicate its inductance value.

Power Supply Transformer

A photo of a collection of cut wires
A photo of a yellow element on a circuit board.

This transformer has multiple sets of windings and is used in a power supply to create multiple output AC voltages from a single AC input such as a wall outlet.

The small wires nearer the center are “high impedance” turns of magnet wire. These windings carry a higher voltage but a lower current. They’re protected by several layers of tape, a copper-foil electrostatic shield, and more tape.

The outer “low impedance” windings are made with thicker insulated wire and fewer turns. They handle a lower voltage but a higher current.

All of the windings are wrapped around a black plastic bobbin. Two pieces of ferrite ceramic are bonded together to form the magnetic core at the heart of the transformer.

This article appears in the February 2023 print issue.