PSSST! Here’s A Novel SSB Radio Design With Only Seven Transistors

November 20, 2021 by Ryan Flowers 41 Comments

When [Pete Juliano] sat down to design a sideband transceiver for the 20 Meter (14 MHz) ham radio band, he eschewed the popular circuits that make up so many designs. He forged ahead, building a novel design that he calls Pete’s Simple Seven SSB Transceiver, or PSSST for short.

What makes the PSSST so simple is not only its construction, but the low component count. The same circuit using four 2N2222A’s is used on both transmit and receive. On transmit, an extra three components step in to amplify the microphone input and build output power, which is 2.5-4 Watts, depending on the final output transistor used. The best part is that all of the transistors can be had for under $10 USD! [Pete] shows where radio components such as the RF mixers and the crystal filter can be purchased, saving a new constructor a lot of headaches. The VFO and IF frequencies are both provided by the venerable si5351a with an Arduino at the helm.

Many simple transceivers are designed to demonstrate a minimum viable radio, with performance not really a goal. On the other hand, the PSSST was modeled stage-by-stage in LTSpice, ensuring great transmit audio and nice receiver performance. Be sure to check out the demonstration below the break!

[Pete] has painstakingly documented the entire project on his website, and the code for the VFO is available by request via email. We appreciate this contribution to the homebrew ham radio community, and we’re sure this will provide many nights of solder smoking enjoyment for radio amateurs around the world.

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FlowIO Takes Top Honors In The 2021 Hackaday Prize

November 20, 2021 by Dan Maloney 8 Comments

FlowIO Platform, a modular pneumatics controller for soft robotics and smart material projects, took home Grand Prize honors at the 2021 Hackaday Prize. Aside from the prestige of coming out on top of hundreds of projects and bragging rights for winning the biggest hardware design challenge on Earth, the prize carries an award of $25,000 and a Supplyframe DesignLab residency to continue project development. Four other top winners were also announced at the Hackaday Remoticon virtual conference on Saturday evening.

In a year full of challenges, this year’s Hackaday Prize laid down yet another gauntlet: to “Rethink, Refresh, and Rebuild.” We asked everyone to take a good hard look at the systems and processes that make the world work — or in some cases, not work — and reimagine them from a fresh perspective. Are there better ways to do things? What would you come up with if you started from a blank piece of paper? How can you support and engage the next generation of engineers, and inspire them to take up the torch? And what would you come up with if you just let your imagination run wild?

And boy, did you deliver! With almost 500 entries, this year’s judges had quite a task in front of them. Each of the five challenges — Refresh Displays, Rethink Work-From-Home Life, Reimagine Supportive Tech, Redefine Robots, and Reactivate Wildcard — had ten finalists, which formed the pool of entries for the overall prize. And here’s what they came up with.

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Cheating A Pedometer The Easy Way

November 20, 2021 by Lewin Day 9 Comments

These days, pedometers are integrated into just about every smartwatch on the market, and some of the dumber ones too. Tracking step counts has become a global pastime, and at times, a competitive one. However, any such competition can easily be gamed, as demonstrated by [Luc Volders].

Generally, all it takes to fool a basic pedometer is a gentle rhythmic jiggling motion of some sort. Cheaper devices will even register steps with little more than vague shaking.

[Luc] exploited this with basic machinery. A servo’s output shaft is fitted with a 3D printed cylinder, sized to allow a smartwatch to be attached as if to a wrist. Then, a Raspberry Pi Pico simply rocks the servo back and forth at regular intervals, and the watch begins counting these ersatz steps. Looking at the project as a whole, we’re betting [Luc] took some inspiration from old-fashioned automatic watch winders.

It’s hard to envision an important application for this technology. However, if one is in a friendly competition with friends who don’t scrutinize the results too closely, this would be an easy way to win.

Alternatively, consider building a pedometer to track your hamster’s exercise regime. If you’ve got your own exercise hacks on the go, drop us a line!

The (Sodium Chloride) Crystal Method

November 20, 2021 by Al Williams 25 Comments

[Chase’s] post titled “How to Grow Sodium Chloride Crystals at Home” might as well be called “Everything You Always Wanted to Know about Salt Crystals (but Were Afraid to Ask).” We aren’t sure what the purpose of having transparent NaCl crystals are, but we have to admit, they look awfully cool.

Sodium chloride, of course, is just ordinary table salt. If the post were simply about growing random ugly crystals, we’d probably have passed over it. But these crystals — some of them pretty large — look like artisan pieces of glasswork. [Chase] reports that growing crystals looks easy, but growing attractive crystals can be hard because of temperature, dust, and other factors.

You probably have most of what you need. Table salt that doesn’t include iodine, a post, a spoon, a funnel, filter paper, and some containers. You’ll probably want tweezers, too. The cooling rate seems to be very important. There are pictures of what perfect seed crystals look like and what happens when the crystals form too fast. Quite a difference! Once you find a perfectly square and transparent seed crystal, you can use it to make bigger ones.

After the initial instructions, there is roughly half the post devoted to topics like the effect growth rate has on the crystal along with many pictures. There are also notes on how to form the crystals into interesting shapes like stars and pyramids. You can also see what happens if you use iodized salt.

If salt is too tame for you, try tin. Or opt for copper, if you prefer that.

The Pros And Cons Of A Power Flush Toilet

November 20, 2021 by Lewin Day 36 Comments

By and large, toilet design hasn’t radically changed in a good long time. The problem was considered solved, and society moved on. However, [Handy Geng] was tasked by a friend to build a toilet with an extra-powerful flush, so he went ahead and did just that.

The concept is simple; the water tank in the custom-built toilet can be charged with pressurized air from a compressor when an more powerful flush is needed. Then, when the lever is pulled on that flush, the water will blast into the bowl with significantly more ferocity than usual.

[Handy Geng] also notes a further benefit from the system. By bolting down the toilet lid, using a gasket to seal it to the toilet bowl, the air pressure system can be used to blast out blockages and clogs.

However, there are some drawbacks. The toilet is nearly entirely constructed out of steel, a material that generally isn’t the first choice when working with water or bodily fluids. Additionally, the power flush mode tends to end up with water spraying out of the bowl due to the intensity of the spray.

Regardless, it goes to show that the toilet design is still an active area of research, and that we needn’t settle for the toilets we have today. More powerful, more capable models are just around the corner if we want them. Video after the break.

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Hackaday Remoticon: What’s Happening Right Now

November 20, 2021 by Mike Szczys 1 Comment

Here’s what you need to know to take part in the Hackaday Remoticon Today.

Watch all of today’s talks on the live stream
Interact with everyone by joining Discord

Notable Events:

All talk and schedule information is available on the conference webpage, but here are the things you don’t want to miss (all times are Pacific time zone):

10:10 am | Keynote: Keith Thorne
5:25 pm | Keynote: Jeremy Fielding
6:25 pm | Hackaday Prize Ceremony
7:35pm | After party live set from DJ Jackalope — watch on Twitch, socialize on Discord

Remoticon Is On!

November 20, 2021 by Elliot Williams No comments

If you’re reading this post while the bits are still fresh, you’ve got about four hours until day two of Hackaday Remoticon 2021. You can feel the electricity in the air, right? We’ve got an absolutely stellar line-up this year: every talk is gonna be a good talk.

Friday was great fun, and you can still still rewind Friday’s live stream if you hurry. Otherwise, at 11:00 AM PST, we’ll start up day two with a keynote talk by Keith Thorne, who’s going to take us through all of the work, and hacks, that made the LIGO experiment the most sensitive instrument mankind has ever made. Bookending the talks, just before the Hackaday Prize announcement and after-party DJ Jackalope Live Set, Jeremy Fielding is going to be walking through everything about his robotic arm and what you need to know about anything that moves.

Watch some great talks, and then hang out with the presenters afterwards over on our Discord server. What more do you want on a Saturday?

We really don’t want you to miss out on anything, but in case you come late to the talks, you can rewind the live stream to catch up. After it’s all done, we’ll slice and dice up the talks so you can find them later. But if you miss out on the discussions, the chance to ask our speakers questions, and the pervasive Jolly Wrencher ambiance, you’ve just missed out. Join us live if you possibly can! We’d love to see you.