Hackaday Links: April 29, 2018

Amazon has released the Echo Dot Kids Edition, an always-on, Internet-connected microphone. According to Amazon’s Children’s Privacy Disclosure, the Amazon Echo Dot Kids Edition collects data such as, ‘name, birthdate, contact information (including phone numbers and email addresses), voice, photos, videos, location, and certain activity and device information. The Amazon Echo Dot Kids Edition is able to read audiobooks for bedtime reading and teaches your children to live in a dystopian panopticon of Orwellian proportions. It comes in green, red, and blue.

Kim Possible! The biggest news headline this week is the coming end of the Korean War. The peninsula has been in a state of war since 1950, but leaders from both countries have agreed to negotiate a treaty to replace the 60-year-old truce. There is also an agreement between the two countries for complete denuclearization. This is great news for Hackaday. Every day, we’re eyeing our North Korean readership. Some days we get a view, some days we don’t, but year over year we’re always getting more views. Will this treaty result in even more Hackaday readers in North Korea? Only time will tell. Here’s some music. It wasn’t a chicken.

The East Coast RepRap Festival is on. Inspired by the Midwest RepRap Festival, the ERRF is happening north of Baltimore on June 23rd and 24th. What’s it going to be like? Nobody knows! This is the first time ERRF is happening, but judging by MRRF standards, it should be awesome. Also, crab season.

One of the most interesting hacks of this year is [Steve Markgraf]’s tool to allow transmit-only SDR through cheap USB 3.0 to VGA adapters. The hack relies on the Fresco Logic FL2000 chip and gives you the ability to transmit FM, TVB-T, and create your own GSM cell site. You can also spoof GPS to get something besides a rattata in Pokemon Go or hack your ankle bracelet to keep your parole officer off your back. The open question, though, is which USB to VGA adapter has the FL2000 chipset. I can confirm this one on Amazon has the relevant chipset. It’s a bit expensive at $15 (the same chipset is available from the usual eBay and AliExpress suppliers for $6), but if you’re looking for something that is available with Prime, there you go. Now we’re looking for shared OSH Park projects with a VGA input on one end and some antennas on the other. Make it happen, people.

Supercapacitors are awesome, but is it possible to fly a drone with a bank of them? Sure, for about 10 seconds. [dronelab] built a 7-cell, 200F supercap and managed to fly a little racing quad for about ten seconds. Not terribly great, but this is going to be awesome when we get multi-thousand Farad superultramegacaps.

Like Open Hardware? The Open Source Hardware Association is opening up the Ada Lovelace Fellowship for women, LGTBA+ and other minorities to attend the Open Hardware Summit. The deadline is tomorrow, so do it soon.

M3D has announced a new 3D printer that can print with four filaments. The Crane Quad is your basic i3 ripoff with an interesting extruder. It looks like it uses four tiny motors to feed filament into the main extruder motor. This isn’t really anything new; the Prusa i3 multimaterial upgrade does the same thing. However, M3D claims they have mastered color mixing. The Prusa upgrade doesn’t do mixing, and this is most likely the reason it works so well. Can M3D pull it off? This is a very, very, very hard problem.

Fail Of The Week: An Electric Bicycle, Powered By AA Batteries

Very slowly, some very cool parts are coming out on the market that will make for some awesome builds. Supercapacitors are becoming a thing, and every year, the price of these high power supercaps go a little lower, and the capacity gets a little higher. It’s really only a matter of time before someone hacks some supercaps into an application that’s never been seen before. The Navy is doing it with railguns, and [David] is building an electric bike, powered by AA batteries. While [David]’s bike technically works with the most liberal interpretation of ‘technically’, it’s the journey that counts here.

This project began as an investigation into using supercapacitors in an electric bicycle. Supercaps have an energy density very much above regular capacitors, but far behind lithium cells. Like lithium cells, they need a charge balancer, but if you manage to get everything right you can trickle charge them while still being able to dump all that power in seconds. It’s the perfect application for a rail gun, or for slightly more pedestrian applications, an electric bike with a hill assist button. The idea for this build would be to charge supercaps from a bank of regular ‘ol batteries, and zoom up a hill with about fifteen seconds of assistance.

The design of the pulsed power DC supply is fairly straightforward, with a mouthful of batteries feeding the supercap array through boost regulators, and finally going out to the motor through another set of regulators. Unfortunately, this project never quite worked out. Everything worked; it’s just this isn’t the application for the current generation of supercapacitors. There’s not enough energy density in [David]’s 100F supercaps, and the charging speed from a bunch of AA batteries is slow. For fifteen minutes of charging, [David] gets about fifteen seconds of boost on his bike. That’s great if you only ever have one hill to climb, but really useless in the real world.

That doesn’t mean this project was a complete failure. [David] now has a handy, extremely resilient array of supercaps that will charge off of anything and provide a steady 24V for a surprising amount of time. Right now, he’s using this scrapped project as a backup power supply for his 3D printer. That 100 Watt heated bed slurps down the electrons, but with this repurposed supercap bank, it can survive a 20 second power outage.

It’s a great project, and even if the technology behind supercaps isn’t quite ready to be used as a boost button on an electric bike, it’s still a great example of DIY ingenuity. You can check out [David]’s demo of the supercap bank in action below.

Continue reading “Fail Of The Week: An Electric Bicycle, Powered By AA Batteries”

Supercapacitor Uses No Carbon

Supercapacitors have found a myriad of uses due to their ability to rapidly charge and then deliver the power efficiently. Currently, production of supercapacitors requires materials made out of carbon which requires high temperatures and poses other manufacturing difficulties.

Researchers announced a new type of supercapacitor that uses no carbon and could have advantages over conventional technologies. The new research focuses on metal-organic frameworks, or MOFs. This material is extremely porous with a sponge-like structure. Since supercapacitors require large surface areas, that makes MOFs an interesting material for that application. However, MOFs are not very electrically conductive, which is a disadvantage.

Continue reading “Supercapacitor Uses No Carbon”

Ask Hackaday: Graphene Capacitors On Kickstarter

Last week, we heard of an interesting Kickstarter that puts a capacitor and charging circuit in the same space as a AA battery. This is usually a very simple endeavour, but this capacitor has the same energy density as an alkaline cell. The chemistry inside this capacitor was initially attributed to lithium ion, and a few people in the comments section were wondering how this was possible. The math just didn’t seem to add up.

The guy behind this Kickstarter, [Shawn West], recently spilled the beans on these… interesting capacitors. Apparently, they’re not lithium ion capacitors at all, but graphene capacitors. Graphene capacitors you can buy. On Kickstarter. Graphene capacitors, also known as the thing that will change everything from smartphones to electric vehicles, and everything in between. I will admit I am skeptical of this Kickstarter.

Apparently, these graphene supercaps are in part designed and manufactured by [Shawn] himself. He fabricates the graphene by putting graphite powder in a ball mill for a day, adding a bit of water and surfactant, then running the ball mill for another few days. The graphene then floats to the top where it is skimmed off and applied to a nonconductive film.

There’s absolutely nothing that flies in the face of the laws of physics when it comes to graphene capacitors – we’ve seen a few researchers at UCLA figure out how to make a graphene supercap. The general consensus when it comes to graphene supercaps is something along the lines of, ‘yeah, it’ll be awesome, in 10 years or so.’ I don’t think anyone thought the first graphene capacitors would be available through Kickstarter, though.

I’m a little torn on this one. On one hand, graphene supercaps, now. On the other hand, graphene supercaps on Kickstarter. I’m not calling this a scam, but if [Shawn]’s caps are legit, you would think huge companies and governments would be breaking down his door to sign licensing agreements.

Post your thoughts below.

Hackaday Links: April 27, 2014



The HackFFM hackerspace in Frankfurt finally got their CO2 laser up and running, and the folks there were looking for something to engrave. They realized the labels on IC packages are commonly laser engraved, so they made a DIP-sized Arduino. The pins are labelled just as they would be on an Arduino, and a few SMD components dead bugged onto the pins provide all the required circuitry. Video here.

A few years ago, we heard [David Mellis] built a DIY cell phone for an MIT Media Lab thingy. Apparently it’s making the blog rounds again thanks to the Raspi cell phone we featured yesterday. Here’s the Arduino cell phone again. Honestly we’d prefer the minimalist DIY Nokia inspired version.

The Raspberry Pi is now a form factor, with the HummingBoard, a Freescale i.MX6-powered clone, being released soon. There’s another form factor compatible platform out there, the Banana Pi, and you can actually buy it now. It’s an ARM A20 dual core running at 1GHz, Gig of RAM, and Gigabit Ethernet for about $60. That SATA port is really, really cool, too.

[Richard] has been working on a solar-powered sun jar this winter and now he’s done. The design uses two small solar panels to charge up two 500F (!) supercapacitors. There’s a very cool and very small supercap charging circuit in there, and unless this thing is placed in a very dark closet, it’ll probably keep running forever. Or until something breaks.

Here’s something awesome for the synth heads out there: it’s an analog modeling synthesizer currently on Indiegogo. Three DCOs, 18dB lowpass filter, 2 envelopes and an LFO, for all that classic Moog, Oberheim, and Roland goodness. It’s also pretty cheap at $120 USD. We really don’t get enough synth and musical builds here at Hackaday, so if you’re working on something, send it in.

A glass-based PCB? Sure. Here’s [Masataka Joei] put gold and silver on a piece of glass, masked off a few decorative shapes, and sandblasted the excess electrum away. [Masataka] is using it for jewelery, but the mind races once you realize you could solder stuff to it.