The weaving is on the left, a microphoto of the chip die is on the right.

The 555 As You’ve Never Seen It: In Textile!

The Diné (aka Navajo) people have been using their weaving as trade goods at least since European contact, and probably long before. They’ve never shied from adopting innovation: churro sheep from the Spanish in the 17th century, aniline dies in the 19th, and in the 20th and 21st… integrated circuits? At least one Navajo Weaver, [Marilou Schultz] thinks they’re a good match for the traditional geometric forms. Her latest creation is a woven depiction of the venerable 555 timer.

“Popular Chip” by Marilou Schultz. Photo courtesy of First American Art Magazine, via righto.com

This isn’t the first time [Marilou] has turned an IC into a Navajo rug; she’s been weaving chip rugs since 1994– including a Pentium rug commissioned by Intel that hangs in USA’s National Gallery of Art–but it’s somehow flown below the Hackaday radar until now. The closest thing we’ve seen on these pages was a beaded bracelet embedding a QR code, inspired by traditional Native American forms.

That’s why we’re so thankful to [VivCocoa] for the tip. It’s a wild and wonderful world out there, and we can’t cover all of it without you. Are there any other fusions of tradition and high-tech we’ve been missing out on? Send us a tip.

2025 One Hertz Challenge: Digital Clock Built With Analog Timer

You can use a microcontroller to build a clock. After all, a clock is just something that counts the passage of time. The only problem is that microcontrollers can’t track time very accurately. They need some kind of external timing source that doesn’t drift as much as the microcontroller’s primary clock oscillator. To that end, [Josh] wanted to try using a rather famous IC with his Arduino to build a viable timepiece.

[Josh]’s idea was straightforward—employ a 555 timer IC to generate a square wave at 1 Hz. He set up an Arduino Uno to count the pulses using edge detection. This allowed for a reliable count which would serve as the timebase for a simple 24-hour clock. The time was then displayed on an OLED display attached over I2C, while raw pulses from the 555 were counted on a 7-segment display as a useful debugging measure. Setting the time is easy, with a few pushbuttons hooked up to the Arduino for this purpose.

[Josh] claims a drift of “only ~0.5 seconds” but does not state over what time period this drift occurs. In any case, 555s are not really used for timekeeping purposes in this way, because timers based on resistor-capacitor circuits tend to drift a lot and are highly susceptible to temperature changes. However, [Josh] could easily turn this into a highly accurate clock merely by replacing the 555 square wave input with a 1PPS clock source from another type of timer or GPS device.

We’ve had quite a few clocks entered into the One Hertz Competition already, including this hilariously easy Nixie clock build. You’ve got until August 19 to get your own entry in, so wow us with your project that does something once a second!

2025 One Hertz Challenge: A 555, But Not As We Know It

We did explicitly ask for projects that use a 555 timer for the One Hertz Challenge, but we weren’t expecting the 555 to be the project. Yet, here we are, with [matt venn]’s Open Source 1Hz Blinky, that blinks a light with a 555 timer… but not one you’d get from Digikey. 

Hooking a 555 to blink an LED at one hertz is a bog-simple, first-electronics-project type of exercise, unless you have to make the 555 first. Rather than go big, as we have seen before, [matt venn] goes very small, with a 555 implemented on a tiny sliver of Tiny Tapeout 6.

We’ve covered projects using that tapeout before, but in case you missed it, Tiny Tapeout gives space to anyone to produce ASICs on custom silicon using an open Process Design Kit, and we have [matt venn] to thank for it. The Tiny Tapeout implementation of the 555 was actually designed by [Vincent Fusco].

Of course wiring it up is a bit more complicated than dropping in a 555 timer to the circuit: the Tiny Tapeout ASIC must be configured to use that specific project using its web interface.  There’s a demo video embedded below, with some info about the project– it’s not just a blinking LED, so it’s worth seeing. The output isn’t exactly One Hertz, so it might not get the nod in the Timelord category, but it’s going to be a very strong competitor for other 555-based projects– of which we could really use more, hint-hint. You’ve got until August 19th, if you think you can use a 555 to do something more interesting than blink an LED.

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The 555 Writ Large

Few electronic ICs can claim to be as famous as the 555 timer. Maybe part of the reason is that the IC doesn’t have a specific function. It has a lot of building blocks that you can use to create timers and many other kinds of circuits. Now [Stoppi] has decided to make a 555 out of discrete components. The resulting IC, as you can see in the video below, won’t win any prizes for diminutive size. But it is fun to see all the circuitry laid bare at the macro level.

The reality is that the chip doesn’t have much inside. There’s a transistor to discharge the external capacitor, a current source, two comparators, and an RS flip flop. All the hundreds of circuits you can build with those rely on how they are wired together along with a few external components.

Even on [stoppi]’s page, you can find how to wire the device to be monostable, stable, or generate tones. You can also find circuits to do several time delays. A versatile chip now blown up as big as you are likely to ever need it.

Practical? Probably not, unless you need a 555 with some kind of custom modification. But for understanding the 555, there’s not much like it.

We’ve seen macro 555s before. It is amazing how many things you can do with a 555. Seriously.

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Announcing The 2025 Hackaday One Hertz Challenge

It’s about time! Or maybe it’s about time’s reciprocal: frequency. Whichever way you see it, Hackaday is pleased to announce, just this very second, the 2025 One Hertz Challenge over on Hackaday.io. If you’ve got a device that does something once per second, we’ve got the contest for you. And don’t delay, because the top three winners will each receive a $150 gift certificate from this contest’s sponsor: DigiKey.

What will you do once per second? And how will you do it? Therein lies the contest! We brainstormed up a few honorable mention categories to get your creative juices flowing.

  • Timelords: How precisely can you get that heartbeat? This category is for those who prefer to see a lot of zeroes after the decimal point.
  • Ridiculous: This category is for the least likely thing to do once per second. Accuracy is great, but absurdity is king here. Have Rube Goldberg dreams? Now you get to live them out.
  • Clockwork: It’s hard to mention time without thinking of timepieces. This category is for the clockmakers among you. If your clock ticks at a rate of one hertz, and you’re willing to show us the mechanism, you’re in.
  • Could Have Used a 555: We knew you were going to say it anyway, so we made it an honorable mention category. If your One Hertz project gets its timing from the venerable triple-five, it belongs here.

We love contests with silly constraints, because you all tend to rise to the challenge. At the same time, the door is wide open to your creativity. To enter, all you have to do is document your project over on Hackaday.io and pull down the “Contests” tab to One Hertz to enter. New projects are awesome, but if you’ve got an oldie-but-goodie, you can enter it as well. (Heck, maybe use this contest as your inspiration to spruce it up a bit?)

Time waits for no one, and you have until August 19th at 9:00 AM Pacific time to get your entry in. We can’t wait to see what you come up with.

The Magic Touch: A 555 Touch Switch

There seems to be nothing a 555 can’t do. We’ve seen it before, but [electronzapdotcom] reminds us you can use a 555 and a few parts to make a reasonable touch switch in this video, embedded below.

The circuit uses some very large resistors so that noise from your body can overcome the logic level on the trigger and threshold inputs. You can easily adapt this idea if you need a simple touch switch. Though we imagine this circuit wouldn’t work well if you were in a quiet environment. We suspect 50 or 60 Hz hum is coupling through your finger and triggering the pins, but it could be a different effect.

How reliable is it? Beats us. The circuit is a bistable, so essentially your finger pumps a signal into a flip-flop. This is old trick, but could be useful. Of course, if you really need a touch switch, you have plenty of options. You can get little modules. Or, directly measure skin resistance.

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Probably The Simplest Sequencing Synth

With inexpensive microntrollers capable of the most impressive feats of sound synthesis, it’s not so often we see projects that return to an earlier style of electronic music project. The 1-bit synth from [Electroagenda] takes us firmly into that territory, employing that most trusty of circuits, a 555.

It’s a time-honored circuit, a 555 provides a note clock that drives a 4017 that functions as a sequencer. This switches in a set of voltage dividers, which in turn control another 555 oscillator that produces the notes. It’s a fun toy straight from the 1970s, right down to the protoboard and hookup wire construction. There’s a demo video with some lovely beeps below, and we think most of you should have what it takes to make your own.

If you’re seeking more inspiration, may we introduce you to our Logic Noise series?

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