CAD, From Scratch: MakerCAD

August 29, 2025 by Jenny List 29 Comments

It’s likely that many of you use some form of CAD package, but how many of you have decided you didn’t like the software on offer? [Marcus Wu] did, and instead of griping, he wrote his own CAD software. It’s called MakerCAD, it’s published under an MIT licence, and you can try it yourself.

It’s written in Go, and it’s superficially similar to OpenSCAD in that the interface is through code. The similarity is skin deep though, as it provides the user with constraint solving as described in the video below the break.

As it stands it’s by no means feature complete, but it is now at a point at which it can be evaluated. Simple models can be created and exported as STEP files, so it can be used as a real-world CAD tool.

Whether it will flourish is down to the path it takes and how its community guides it. But we’re pleased to see any new open source projects in this space, which remains overly dominated by proprietary packages. If you try it, write up your experiences, we’d love to see how this develops.

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Pi Port Protection PCB

August 25, 2025 by Jenny List 16 Comments

We’re used to interfaces such as I2C and one-wire as easy ways to hook up sensors and other peripherals to microcontrollers. While they’re fine within the confines of a small project, they do have a few limitations. [Vinnie] ran straight into those limitations while using a Raspberry Pi with agricultural sensors. The interfaces needed to work over long cable runs, and to be protected from ESD due to lightning strikes. The solution? A custom Pi interface board packing differential drivers and protection circuits aplenty.

The I2C connection is isolated using an ISO1541 bus isolator from TI, feeding a PCA9615DP differential I2C bus driver from NXP. 1-wire is handled by a Dallas DS2482S 1-wire bus master and an ESD protection diode network. Even the 5-volt power supply is delivered through an isolated module.

Whether or not you need this Raspberry Pi board, this is still an interesting project for anyone working with these interfaces. If you’re interested, we’ve looked at differential I2C in the past.

A PLL For Perfect Pitch

August 24, 2025 by Jenny List 5 Comments

When Hackaday runs a contest, we see all manner of clever projects. But inevitably there are some we don’t see, because their builders didn’t manage to get them finished in time. [Park Frazer]’s phase-locked loop is one of them. The circuit is an all-discrete PLL that derives a 440 Hz output from a 1 Hz input, and it arrived just too late for our 1 Hz contest.

If you aren’t familiar with a phase-locked loop, in this context you can think of them as a programmable frequency multiplier. A voltage-controlled oscillator is locked to an input frequency by comparing the two with a phase detector. Multiplication can be achieved by putting a frequency divider between the oscillator and the phase detector. It’s at the same time a complex and easy to understand circuit. In this case, when broken down into a set of multivibrators, it makes sense. The charge pump phase detector is a little different from the XOR gate we were expecting, but as he explains, it’s better.

If PLLs are a mystery, have a look at this video from a [Jeri Ellsworth] and [Bil Herd].

The 32 Bit 6502 You Never Had

August 24, 2025 by Jenny List 43 Comments

In the beginning was the MOS6502, an 8-bit microprocessor that found its way into many famous machines. Some of you will know that a CMOS 6502 was created by the Western Design Center, and in turn, WDC produced the 65C816, a 16-bit version that was used in the Apple IIgs as well as the Super Nintendo. It was news to us that they had a 32-bit version in their sights, but after producing a datasheet, they never brought it to market. Last October, [Mike Kohn] produced a Verilog version of this W65C832 processor, so it can be experienced via an FPGA.

The description dives into the differences between the 32, 16, and 8-bit variants of the 6502, and we can see some of the same hurdles that must have faced designers of other chips in that era as they moved their architectures with the times while maintaining backwards compatibility. From our (admittedly basic) understanding it appears to retain that 6502 simplicity in the way that Intel architectures did not, so it’s tempting to imagine what future might have happened had this chip made it to market. We’re guessing that you would still be reading through an Intel or ARM, but perhaps we might have seen a different path taken by 1990s game consoles.

If you’d like to dive deeper into 6502 history, the chip recently turned 50.

Thanks [Liam Proven] for the tip.

Candle Oscillator Really Heats Things Up

August 23, 2025 by Jenny List 11 Comments

As the timebase for a clock, almost anything with a periodic oscillation can be used. Traditionally, that meant a pendulum, but in our time, we’ve seen plenty of others. Perhaps none as unusual as [Tim]’s candle flicker clock, though.

Candles are known for their flickering, a property of the wick and the fuel supply that candle manufacturers have gone to great lengths to mitigate. If you bring several of them together, they will have a significant flicker, with a surprisingly consistent 9.9 Hz frequency. This is the timebase for the clock, with the capacitance of the flame being sensed by a wire connected to a CH32 microcontroller, and processed to produce the required timing.

We like this project, and consider it a shame that it’s not an entry in our One Hertz Challenge. Oddly, though, it’s not the first candle-based oscillator we’ve seen; they can even be turned into active electronic devices.

Finding A New Model For Hacker Camps

August 22, 2025 by Jenny List 68 Comments

A nicht scene in a post-apocalyptic future, in this case an electronics bazaar adjacent to the rave area in EMF 2018 Null Sector. — Electromagnetic Field manage to get live music at a hacker camp right, by turning it into the most cyberpunk future possible.

A couple of decades ago now, several things happened which gave life to our world and made it what it has become. Hackerspaces proliferated, giving what was previously dispersed a physical focus. Alongside that a range of hardware gave new expression to our projects; among them the Arduino, affordable 3D printing, and mail-order printed circuit boards.

The result was a flowering of creativity and of a community we’d never had before.Visiting another city could come with a while spent in their hackerspace, and from that new-found community blossomed a fresh wave of events. The older hacker camps expanded and morphed in character to become more exciting showcases for our expression, and new events sprang up alongside them. The 2010s provided me and my friends with some of the most formative experiences of our lives, and we’re guessing that among those of you reading this piece will be plenty who also found their people.

And then came COVID. Something that sticks in my mind when thinking about the COVID pandemic is a British news pundit from March 2020 saying that nothing would be quite the same as before once the pandemic was over. In our community this came home to me after 2022, when the first large European hacker camps made a return. They were awesome in their own way, but somehow sterile, it was as though something was missing. Since then we’ve had a few more summers spent trailing across the continent to hang out and drink Club-Mate in the sun, and while we commend the respective orgas for creating some great experiences, finding that spark can still be elusive. Hanging out with some of my friends round a European hackerspace barbecue before we headed home recently, we tried to put our finger on exactly where the problem lay.

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Bad To The Bluetooth: You Shouldn’t Use This Jammer

August 21, 2025 by Jenny List 12 Comments

Back in the day, an FM bug was a handy way to make someone’s annoying radio go away, particularly if it could be induced to feedback. But these days you’re far more likely to hear somebody’s Bluetooth device blasting than you are an unruly FM radio.

To combat this aural menace, [Tixlegeek] is here with a jammer for the 2.4 GHz spectrum to make annoying Bluetooth devices go silent. While it’s not entirely effective, it’s still of interest for its unashamed jankiness. Besides, you really shouldn’t be using one of these anyway, so it doesn’t really matter how well it works.

Raiding the AliExpress 2.4 GHz parts bin, there’s a set of NRF24L01+ modules that jump around all over the band, a couple of extremely sketchy-looking power amplifiers, and a pair of Yagi antennas. It’s not even remotely legal, and we particularly like the sentence “After running the numbers, I realized it would be cheaper and far more effective to just throw a rock at [the Bluetooth speaker]“. If there’s a lesson here, perhaps it is that effective jamming comes in disrupting the information flow rather than drowning it out.

This project may be illegal, but unlike some others we think it (probably) won’t kill you.