Author: Dan Maloney

3373 Articles

Design For 3D Printing Hack Chat

May 22, 2023 by No comments

Join us on Wednesday, May 24 at noon Pacific for the Design for 3D Printing Hack Chat with Eric Utley!

Like a lot of enabling technologies, 3D printing has had a strange trajectory. It started out as a laboratory oddity, moved on to industrial applications, and finally filtered down to the DIY set, first as scratch-built machines and later as inexpensive commodity printers that can be found almost anywhere. Pretty much everyone who needs a 3D printer now has one.

Not all additive manufacturing technologies are created equal, though, and there are plenty of applications for 3D printed parts where FDM just won’t cut it. Luckily, any of us can get access to the latest and greatest manufacturing technologies through job houses that specialize in everything from metal 3D printing to sheet metal fabrication, CNC machining, and even small-run injection molding. We may not be able to afford any of the machines, but in a lot of cases we can afford to rent time of them and get high-quality parts quickly.

join-hack-chatBut that raises another question: Is my design ready for printing? What works on an Ender on your shop bench might not quite translate to the latest SLS printer, and sending off an iffy design could just end up wasting time and money. Whether you’re sending your designs out and running them up on your own printer, you want to know what you’re doing will work. That’s why we’ve asked Eric Utley, an applications engineer with Protolabs, to stop by the Hack Chat. With 12 years of additive manufacturing experience, he’ll be able to help you tune up your designs and make sure they’re ready to print.

Our Hack Chats are live community events in the Hackaday.io Hack Chat group messaging. This week we’ll be sitting down on Wednesday, May 24 at 12:00 PM Pacific time. If time zones have you tied up, we have a handy time zone converter.

Click that speech bubble to the right, and you’ll be taken directly to the Hack Chat group on Hackaday.io. You don’t have to wait until Wednesday; join whenever you want and you can see what the community is talking about.

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Hackaday Links: May 21, 2023

May 21, 2023 by 14 Comments

The reports of the death of automotive AM radio may have been greatly exaggerated. Regular readers will recall us harping on the issue of automakers planning to exclude AM from the infotainment systems in their latest offerings, which doesn’t seem to make a lot of sense given the reach of AM radio and its importance in public emergencies. US lawmakers apparently agree with that position, having now introduced a bipartisan bill to require AM radios in cars. The “AM for Every Vehicle Act” will direct the National Highway Transportation Safety Administration to draw up regulations requiring every vehicle operating on US highways to be able to receive AM broadcasts without additional fees or subscriptions. That last bit is clever, since it prevents automakers from charging monthly fees as they do for heated seats and other niceties. It’s just a bill now, of course, and stands about as much chance of becoming law as anything else that makes sense does, so we’re not holding our breath on this one. But at least someone recognizes that AM radio still has a valid use case.

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Op-Amp Challenge: MOSFETs Make This Discrete Op Amp Tick

May 20, 2023 by 9 Comments

When it comes to our analog designs, op-amps tend to be just another jellybean part. We tend to spec whatever does the job, and don’t give much of a thought as to the internals. And while it doesn’t make much sense to roll your own op-amp out of discrete components, that doesn’t mean there isn’t plenty to be learned from doing just that.

While we’re more accustomed to seeing [Mitsuru Yamada]’s digital projects, he’s no stranger to the analog world. In fact, this project is a follow-on to his previous bipolar transistor op-amp, which we featured back in 2021. This design features MOSFETs rather than BJTs, but retains the same basic five-transistor topology as the previous work, with a differential pair input stage, a gain stage, and a buffer stage. Even the construction of the module is similar, using his trademark perfboard and ultra-tidy wiring.

Also new is a flexible evaluation unit for these discrete op-amp modules. This very sturdy-looking circuit provides an easy way to configure the op-amp for testing in inverting, non-inverting, and transimpedance mode, selecting from a range of feedback resistors, and even provides a photodiode input. The video below shows the eval unit in action with the CMOS module, as well as highlights the excellent construction [Mitsuru Yamada] is known for.

Looking for some digital goodness? Check out the PERSEUS-8, a 6502 machine we wish had been a real product back in the day.

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Spy Transceiver Makes Two Tubes Do The Work Of Five

May 19, 2023 by 26 Comments

Here at Hackaday, we love following along with projects as they progress. That’s especially true when a project makes a considerable leap in terms of functionality from one version to another, or when the original design gets more elegant. And when you get both improved function and decreased complexity at the same time? That’s the good stuff.

Take the recent improvements to a vacuum tube “spy radio” as an example. Previously, [Helge (LA6NCA)] built both a two-tube transmitter and a three-tube receiver, either of which would fit in the palm of your hand. A little higher math seems to indicate that combining these two circuits into a transceiver would require five tubes, but that’s not how hams like [Helge] roll. His 80-m CW-only transceiver design uses only two tubes and a lot of tricks, which we admit we’re still wrapping our heads around. On the receive side, one tube serves as a mixer/oscillator, combining the received signal with a slightly offset crystal-controlled signal to provide the needed beat frequency. The second tube serves as the amplifier, both for the RF signal when transmitting, and for audio when receiving.

The really clever part of this build is that [Helge] somehow stuffed four separate relays into the tiny Altoids tin chassis. Three of them are used to switch between receive and transmit, while the fourth is set up as a simple electromagnetic buzzer. This provides the sidetone needed to effectively transmit Morse code, and is about the simplest way we’ve ever seen to address that need. Also impressive is how [Helge] went from a relatively expansive breadboard prototype to a much more compact final design, and how the solder was barely cooled before he managed to make a contact over 200 km. The video below has all the details.

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Hackaday Podcast 219: Lots Of Lasers, Heaps Of Ham Radio, And Breaching The Blood Brain Barrier

May 19, 2023 by No comments

Elliot and Dan teamed up for the podcast this week, bringing you the week’s sweetest hacks. And news too, as the ESA performed a little percussive maintenance on a Jupiter-bound space probe, and we learned about how to get an Orwellian free TV that exacts quite a price. We talked about Bitcoin mining two ways, including a way to put all that waste heat to good use — just don’t expect it to make good financial sense. Why would you stuff zip ties into a hot glue gun? It might just help with plastic repair. Lugging a tube transmitter up a mountain doesn’t sound like a good idea, but with the right design, it’s a lot of fun — and maybe you’ll be better able to tap into Schumann resonances while you’re up there.

Check out the links below if you want to follow along, and as always, tell us what you think about this episode in the comments!

Download a long series of ones and zeroes that, when appropriately interpreted, sound like two people talking about nerdy stuff!

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Hackaday Links: May 14, 2023

May 14, 2023 by 13 Comments

It’s been a while since we heard from Dmitry Rogozin, the always-entertaining former director of Roscosmos, the Russian space agency. Not content with sending mixed messages about the future of the ISS amid the ongoing war in Ukraine, or attempting to hack a mothballed German space telescope back into action, Rogozin is now spouting off that the Apollo moon landings never happened. His doubts about NASA’s seminal accomplishment apparently started while he was still head of Roscosmos when he tasked a group with looking into the Apollo landings. Rogozin’s conclusion from the data his team came back with isn’t especially creative; whereas some Apollo deniers go to great lengths to find “scientific proof” that we were never there, Rogozin just concluded that because NASA hasn’t ever repeated the feat, it must never have happened.

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Reverse Engineering An Oil Burner Comms Board, With A Few Lucky Breaks

May 11, 2023 by 3 Comments

Here’s a question for you: How do you reverse engineer a circuit when you don’t even have it in hand? It’s an interesting problem, and it adds a level of difficulty to the already iffy proposition that reverse engineering generally presents. And yet, not only did [themole] find a way to replicate a comms board for his oil burner, he extended and enhanced the circuit for integration into his home automation network.

By way of backstory, [themole] has a wonky Buderus oil burner, which occasionally goes into safety mode and shuts down. With one too many cold showers as a result, he looked for ways to communicate with the burner controller. Luckily, Buderus sells just the thing — a serial port module that plugs into a spare slot in the controller. Unluckily, the board costs a bundle, and that’s even if you can find it. So armed with nothing but photos of the front and back of the board, the finding of which was a true stroke of luck, he set about figuring out the circuit.

With only a dozen components or so and a couple of connectors, the OEM board gave up its secrets pretty easily; it’s really just a level shifter to make the boiler talk RS-232. But that’s a little passé these days, and [the78mole] was more interested in a WiFi connection. So his version of the card includes an ESP32 module, which handles wireless duties as well as the logic needed to talk to the burner using the Buderus proprietary protocol. The module plugs right into the burner controller and connects it to ESPHome, so no more cold showers for [themole].

We thought this one was pretty cool, especially the way [themole] used the online photos of the board to not only trace the circuit but to get accurate — mostly — measurements of the board using an online measuring tool. That’s a tip we’ll keep in our back pocket.

Thanks to [Jieffe] for the tip.