A homebrew telephone connects home and workshop.

The Calls Are Coming From Inside The House (or Workshop)

October 19, 2021 by Kristina Panos 16 Comments

Hot on the heels of their carbon microphone build a few years ago, [Simplifier] strung up a two-phone network between the house and the workshop. Both telephones are completely DIY except for the pair of switches on the front. Each side has a bell, a microphone, and an audio transformer. Listening is done through a pair of headphones, and both users speak through a homebrew carbon microphone.

We particularly love the bell, which is made from fence post caps. Sitting between the bells and ready to strike is a ball bearing mounted on a really thick piece of wire that’s driven by an electromagnet. To make a call, you use both switches — the one on the left pulls either the bell or the microphone to ground, while the switch on the ~~left~~ right is used momentarily to send 6 V from the lantern battery down the 50 ft. line to the other phone to ring it. You’ll see what we mean in the demo video after the break. Check out the sound of those fence post caps!

[Simplifier] wound an audio transformer that provides the necessary impedance matching to use regular headphones as receivers. Since the homebrew microphones only need 1.5 V, [Simplifier] split the voltage across two carbon contacts placed in series. That’s still more than necessary, but [Simplifier] was able to make it work.

More recently, [Simplifier] has built a beautiful and even better carbon microphone and even hosted a back-to-basics Hack Chat.

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They Milk Cows, Don’t They?

October 18, 2021 by Kristina Panos 90 Comments

You’ve no doubt heard of the many alternatives to cow’s milk that are available these days. Perhaps you’ve even tried a few of them in your quest to avoid lactose. Some coffeehouses have already moved on from soy milk, offering only oat or almond milk instead of 2% and whole. Their reasoning is that soy milk is a highly processed product that can’t be traced back to a single source, which stands in stark contrast to all those bags of single-origin coffee beans.

These nut-based alternatives kicked off what is known as the milk wars — the dairy industry’s fight against labeling plant-based dairy alternatives as ‘milk’ and so on. Well, now it’s getting even more interesting. A company called Perfect Day is making milk using microorganisms that secrete milk proteins. It may sound kind of gross, but it’s essentially microbial fermentation, which is the normal process by which bread, cheese, yogurt, wine, and beer are made.

To be fair, what Perfect Day and other companies are doing is precision fermentation using genetically engineered microorganisms in a bioreactor, so it’s a bit more involved than what you could probably pull off in the basement. Precision fermentation lies somewhere between two modern extremes — plant-based meat and cultured meat. The latter is actual animal tissue grown from stem cells, and is only available at high-end restaurants for exorbitant prices.

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Hackaday Remoticon: Call For Proposals Extended To October 20th

October 15, 2021 by Kristina Panos No comments

In just a few short weeks, we’ll all be meeting up online for the second Hackaday Remoticon on November 19th and 20th. This is the year of the Talk, and who better than you, dear reader, to give one? Good news — we’ve extended the deadline for proposals to Wednesday, October 20th. We’ve all got at least one or two subjects that we could happily bloviate about for hours, be it hardware, software, skill sets, or the stuff that inspires you to stop dreaming and start doing. Why not share your wit and wisdom with the rest of the community?

So, what are you waiting for? Submit your talk proposal today! We’re not looking for you to pack the whole talk into the description box, but we would like to know what your talk will be about, and why it’s relevant to an audience of geeks, hackers, and engineers. Talks are typically 30 minutes in length, but we can likely accommodate shorter or longer talks if needed.

Everyone has something worth sharing, and the fact is, we are always looking for first-time speakers to showcase. Just share the things you’re doing that you’re passionate about, and you’re bound to have a great talk that generates excitement all around.

So grab some go-juice and start brainstorming the outline of your talk — give us enough information that we’ll be thirsty for more. Have you got terrible stage fright? Then encourage your outgoing hackerspace buddy to give one and cheer from the sidelines. Although we would rather see all of you in person, moving this conference online comes with the flexibility to hear from hackers all over the world, and no one has to leave home.

A 3D-printed scale model of the mechanism inside a grand piano.

Printed Piano Mechanism Sure Is Grand

October 14, 2021 by Kristina Panos 9 Comments

Do you know how a piano works? Sure, you press a key and a hammer strikes a string, but what are the finer points of this operation? The intricacy of the ingenious mechanism is laid bare in [Mechanistic]’s 3D-printed scale model of a small section of the grand piano keyboard. The ‘grand’ distinction here is piano length-agnostic and simply refers to any non-upright. Those operate the same way, but are laid out differently in order to save space.

The keys of an acoustic piano are much longer than just the part that shows — they are long levers that do a lot of work, including working their own sound dampeners. The really interesting part is the mechanism that allows a note to be played repeatedly without first releasing the key. This same mechanism also lets the pianist play softly, loudly, or somewhere in between based on the amount of pressure applied.

So you know that the hammer strikes the string (or in this case, the rod), and you can probably figure that it backs off to let the string ring out. But there’s also this whole system that keeps the hammer close by for repeated strikings, as long as the person is holding down the key. Be sure to check it out in the build video after the break.

[Mechanistic] must be going for the standing ovation, because they say in the video’s comments that they will release STL files when they’re finished writing the assembly guide (!). What an encore that will be.

There are many ways to hack an acoustic piano, but don’t go thinking you can sub in guitar strings.

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A tiny TV that shows weather, news, and the classic test pattern.

Tiny TV Tells The Temperature Tale

October 13, 2021 by Kristina Panos 3 Comments

Once upon a time, we would run home from the bus stop to watch Gargoyles and Brady Bunch reruns on the family TV, a late-1970s console Magnavox number that sat on the floor and was about 50% more cabinet than CRT. The old TV, a streamlined white Zenith at least ten years older, had been relegated to the man cave in the basement. It looked so mod compared to the “new” TV, but that’s not the aesthetic my folks were after. They wanted their electronics to double as furniture.

This little TV is a happy medium between the two styles, and for us, it’s all about those feet. But instead of cartoons, it switches between showing the current weather and the top news headlines. Inside that classy oak cabinet is an LCD, an ESP32, and an SD card module. The TV uses OpenWeatherMap and pulls the corresponding weather image from the SD card based on time of day — light images for day, and dark images for night.

We love that it shows the SMPTE color bars, aka the standard American TV test pattern as it switches between weather and news. After showing the top headlines, it automatically switches back to the weather channel. Be sure to check out the short demo video after the break.

Do you like your tiny televisions in strange places? Here’s one you can use to trim your tree this year.

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Illustrated Kristina with an IBM Model M keyboard floating between her hands.

Keebin’ With Kristina: The One With The Curved Typewriter

October 13, 2021 by Kristina Panos 7 Comments

Aerodox Flies on Wireless Wings

[Simon Merrett] didn’t know anything about keyboards when he started this project, but he didn’t let that stop him. [Simon] did what any of us would do — figure out what you like, learn enough to be dangerous, and then start fiddling around, taking all that inspiration and making a mashup of influences that suits your needs.

The Aerodox design became a cross between the ErgoDox‘s key layout and the logic and communication of the Redox Wireless, itself a reduced-size version of the ErgoDox. Interestingly, [Simon] chose the ErgoDox’s dimensions and spacing, and not those of the Redox. Like a lot of people out there, I found the ErgoDox to be too big for my hands, mostly in that the thumb cluster is too far away from the mainland. It’s nice to see that it suits some people, though.

[Simon] worked up a custom hot-swap footprint that makes the board reversible, much like the ErgoDox. Each half has an NRF51822 for a brain, and there’s a third one that acts as a receiver. This external NRF board is connected over UART to an Arduino Pro Micro, which acts as the USB HID and runs QMK. It’s an interesting journey for sure, so go dig into the logs.

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A haptic device that lets visually-impaired people experience the flow and details of dance.

The Beauty Of Dance, Seen Through The Power Of Touch

October 12, 2021 by Kristina Panos 3 Comments

It’s nothing short of amazing what trained dancers can do with their bodies, and a real shame that visually-impaired people can’t enjoy the experience of, say, ballet. For this year’s Hackaday Prize, [Shi Yun] is working on a way for visually-impaired people to experience dance performances via haptic feedback on a special device.

This platform, which is called Kinetic Soul, uses Posenet computer vision to track a dancer’s movements. Posenet detects the dancer’s joints and creates a point map to determine what body parts are moving where, and at what speed. Then the system translates and transmits the movements to the 32 pins on the surface, creating a touchable picture of what’s going on. Each 3D-printed pin is controlled with a solenoid, all of which are driven by a single Arduino.

We think it’s interesting that Kinetic Soul can speak to the user in two different languages. The first is more about the overall flow of a dance, and the second delves into the deconstructed details. Both methods allow for dances to be enjoyed in real time, or via video recording. So how does one deconstruct dance? [Shi Yun] turned to Laban Movement Analysis, which breaks up human locomotion into four broad categories: the body in relation to itself, the effort expended to move, the shapes assumed, and the space used.

[Shi Yun] has been user-testing their ideas at dance workshops for the visually impaired throughout the entire process — this is how they arrived at having two haptic languages instead of one. They plan to continue getting input as they work to fortify the prototype, improve the touch experience, and refine the haptic languages. Check out the brief demonstration video after the break.

Yes indeed, dance is a majestic way of expressing all kinds of things. Think you have no use for interpretive dance? Think again — it can help you understand protein synthesis in an amusing way.

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