When I say “siren” what do you think of? Ambulances? Air raids? Sigh. I was afraid you were going to say that. We’ve got work to do.
You see, the siren played an important role in physics and mathematics about 150 years ago. Through the first half of the 1900s, this fine apparatus was trivialized, used for its pure noise-making abilities. During the World Wars, the siren became associated with air raids and bomb shelters: a far cry from its romantic origins. In this article, we’re going to take the siren back for the Muses. I want you to see the siren in a new light: as a fundamental scientific experiment, a musical instrument, and in the end, as a great DIY project — this is Hackaday after all.
Both of these mods are hacks in the purest sense of the word. The controller mod took a wireless keyboard’s sending circuit board and wedged it inside the NES controller. The original NES controller reads out the buttons into a shift register and sends that down a wire. That’s all gone. [ModPurist] just wired up each button to the sender PCB and figured out which keys they corresponded to on the PC by pressing the buttons. Simple.
The best part of his video about building the controller? After about a minute in, he forgets that he’s filming a technical how-to video and plays Pokemon for the remaining four minutes. That’s the sign of success.
Then there’s the NES hack itself. He stripped everything out, added a Raspberry Pi 2 and a fan, made it all work with the power switch and the original TV outs, and it’s done. Again, nothing more than needs doing, but nothing less. It looks just right plugged up to the CRT monitor (from a C64, no less), and there’s no doubt that being able to play wirelessly on an original NES controller is cool.
Some people collect stamps. Others collect porcelain miniatures. [David Viens] collects voice synthesizers and their ROMs. In this video, he just got his hands on the ultra-rare Electronic Voice Alert (EVA) from early 1980s Chrysler automobiles (video embedded below the break).
Back in the 1980s, speech synthesis was in its golden years following the development of TI’s linear-predictive coding speech chips. These are the bits of silicon that gave voice to the Speak and Spell, numerous video game machines, and the TI 99/4A computer’s speech module. And, apparently, some models of Chrysler cars.
The board appears to have a socket for a TMS-series voice synthesizer chip and another slot for the ROM. It looks like an FTDI 2232 USB-serial converter is being used in bit-bang mode with some custom code driving everything, and presumably sniffing data in the middle. We’d love to see a bunch more detail.
The best part of the video, aside from the ROM-dumping goodness, comes at the end when [David] tosses the ROM’s contents into his own chipspeech emulator and starts playing “your engine oil pressure is critical” up and down the keyboard. Fantastic.
This is weird science. Researchers at Lawrence Berkeley National Laboratory have taken some normal bacteria and made them photosynthetic by adding cadmium sulfide nanoparticles. Cadmium sulfide is what makes the garden-variety photoresistor work. That’s strange enough. But the bacteria did the heavy lifting — they coated themselves in the inorganic cadmium — which means that they can continue to grow and reproduce without much further intervention.
Bacteria are used as workhorses in a lot of chemical reactions these days, and everybody’s trying to teach them new tricks. But fooling them into taking on inorganic light absorbing materials and becoming photosynthetic is pretty cool. As far as we understand, the researchers found a chemical pathway into which the electrons produced by the CdS would fit, and the bacteria took care of the rest. They still make acetic acid, which is their normal behavior, but now they produce much more when exposed to light.
Or if you’d rather make electricity, instead of acetic acid, from your bacteria be our guest. In place of CdS, however, you’ll need a fish. Biology is weird.
[Kripthor] sent us a link to his blog where he writes the Hello World of low-level networking. Basically he’s constructing his own packet and sending it. By itself this isn’t a bad thing. You could use this power for all sorts of networks-diagnostic good. And so, despite the ominous name of his blog post “ESP8266 Jamming”, he’s not really doing anything that bad — he’s just creating many fake WiFi beacon frames and sending them out every so often.
Naturally we wanted to see how he was doing it, and we opened up the Arduino code in GitHub. It turns out that Espressif has written a wifi_send_pkt_freedom() function that just sends out whatever packet you’d like to the network. That was easy.
It also turns out that the ESP8266 will enter monitor mode, where it listens to all WiFi traffic regardless of the MAC address that it’s directed toward. [Pulkin] seems to have done the work for us and posted the code in his GitHub. Now things get nasty. Combining promiscuous monitor mode with some carefully constructed management frames can end up with a classic WiFi deauth denial-of-service attack on a $2 piece of hardware.
We think it’s tremendously cool that the ESP8266 packs such power, and we beg you all to use it responsibly. The last thing we want to see is the world littered with WiFi-DOS throwies. And the last thing you’d want is a visit from the FCC.
Laser sintering works by laying down a thin layer of metal powder and then hitting it with a strong enough laser to sinter the particles together. (Sintering sticks the grains together without getting the metal hot enough to melt it.) The rapid local heating and cooling required to build up 3D objects expands and cools the metal, and can result in stresses inside the resulting object.
The Northwestern team still lays down layers of powder, but glues the layers together with a quick-drying polymer instead of fusing them with a laser. Once the full model is printed, they then sinter it in one piece in an oven.
3D-printed copper lattice. Credit: Ramille Shah and David Dunand
The advantages of adding this extra step are higher printing speed — squirting the liquid out of syringe heads can be faster than fusing metal particles with a laser — and increased structural integrity because the whole model is heated and cooled at one time. A fringe benefit is that the model is still a bit flexible before firing, opening up possibilities for printing a flat model and then bending it into shape before sintering.
And if that weren’t enough, the team figured that they’d add a third step to the procedure to allow it to be used with rust (iron oxide) as the starting powder. They print the rust and polymer model, then un-rust the iron using hydrogen, and then fire it as before. Why rust? Do you know anything cheaper to use as a raw material?
What do you think? The basic idea may even be DIYable — glue metal particles together and heat them up enough to stick. Not in my microwave oven, though. We’d love to see a more energy-efficient 3D metal printer.
The German Patent and Trademark Office has denied the application from UnterhehmerTUM for a trademark on the word “Makerspace”. It wasn’t likely to be a threat to the community anyway, but now it’s entirely off the table. So Kwartzlab Makerspace, Houston Makerspace, Rochester Makerspace, Anchorage Makerspace, … you can all breathe easy!
To be fair, there was never any danger, just a misunderstanding. We reported earlier on the trademark application and within a day or so got an official reply in the comments from Phil (“Mr. Mobile”) Handy that they weren’t looking to enforce anything, but were just essentially trying to make sure that nobody else could pull the rug out from under them. (Thanks [Gentleman Nerd] for pushing them on this.)
The makerspace in question is an open-access offshoot of a business incubator that’s associated with Munich’s Technical University, and it looks like they pumped a couple million Euros into the deal, so there were doubtless layers of bureaucracy that wanted to make sure that their asses were legally covered.
Anyway, the Trademark Office did the right thing, denying the trademark because it wasn’t “unique”, and the makerspace looks awesome. All’s well that ends well.
