Anyone who’s manned a hackerspace booth at an event knows how difficult it can be to describe to people what a hackerspace is. No matter what words you use to describe it, nothing really seems to do it justice. You simply can’t use words to make someone feel that sense of accomplishment and fun that you get when you learn something new and build something that actually works.
[Derek] had this same problem and decided to do something about it. He realized that in order to really share the experience of a hackerspace, he would have to bring a piece of the hackerspace to the people. That meant getting people to build something simple, but fun. [Derek’s] design had to be easy enough for anyone to put together, and inexpensive enough that it can be produced in moderate quantities without breaking the bank.
[Derek] ended up building a simple “optical theremin”. The heart of this simple circuit is an ATTiny45. Arduino libraries have already been ported to this chip, so all [Derek] had to do was write a few simple lines of code and he was up and running. The chip is connected to a photocell so the pitch will vary with the amount of light that reaches the cell. The user can then change the pitch by moving their hand closer or further away, achieving a similar effect to a theremin.
[Derek] designed a simple “pcb” out of acrylic, with laser cut holes for all of the components. If you don’t have access to a laser cutter to cut the acrylic sheets, you could always build your own. The electronic components are placed into the holes and the leads are simply twisted together. This allows even an inexperienced builder to complete the project in just five to ten minutes with no complicated tools. The end result of his hard work was a crowded booth at a lot of happy new makers. All of [Derek’s] plans are available on github, and he hopes his project will find use at Makerfaires and hackerspace events all over the world.
[Jan Rychter] was sick and tired of not being able to find the right power supply for his Nixie tube projects, so he decided to design his own. [Jan] started out designing around the MAX1771 (PDF) DC-DC controller, but quickly discovered he was having stability problems. Even after seven board revisions, he was still experiencing uncontrolled behavior. He ended up abandoning the MAX1171 and switching to the Texas Instruments TPS40210. After three more board designs, he finally has something that works for him. [Jan] admits that his design is likely not perfect (could have fooled us!), but he wanted to release it to the world as Open-Source Hardware to give back to the community.
The end result of [Jan’s] hard work is a 5cm x 5cm board that generates four separate output voltages from a single 12V source. These include both a 3.3V and 5V output for digital logic as well as a 220V out put for Nixie tubes and a 440V maximum output for dekatrons. The circuit also features several safety features including over-current protection, thermal shutdown, and slow-start. Be sure to check out [Jan’s] webpage to view out the schematics and technical information for this awesome circuit.
Need some Nixie tubes to go with that circuit? We know some resources for you to check out. Or you could always just build your own. How can you use this board in your next project?
We’ve seen a few builds from the Flite Test guys before, like a literal flying toaster, airsoft guns mounted to planes, and giving an electric plane an afterburner (that actually produced a little extra thrust). Now the Flite Test crew is gearing up for the Flite Fest, an all things remote-controlled flight convention in Malvern, Ohio during the last weekend in July. Seems like a pretty cool way to spend spend a weekend.
Unless you get one of those fancy resistor kits where every value has its own compartment in a case or plastic baggie, you’ll soon rue the day your loose resistors become disorganized. [Kirll] has an interesting solution to hundreds of loose resistors: packaging tape. If you want a resistor, just grab a pair of scissors.
Okay, these Adafruit “totally not Muppets™” are awesome. The latest video in the Circuit Playground series is titled, “C is for Capacitor“. There’s also “B is for Battery“, because when life gives you lemons, light up an LED. Here’s the coloring book.
A few years ago, a couple of people at the LA Hackerspace Crashspace put together an animated flipbook device – something between a zoetrope and the numbers in those old electromechanical clocks – and launched a kickstarter. Now they’re putting on a show, presented by Giant Robot, featuring the animated art of dozens of artists.
Vintage electronics? Yes. Vintage Soviet electronics? Here’s 140 pages of pictures, mostly of old measurement devices.
How hot are your key components getting? There’s a good chance you’ve built a project and thought: “Well I guess I better slap a heat sink in there to be safe”. But when working on a more refined build you really need to calculate heat dissipation to ensure reliability. This is actually not tough at all. The numbers are right there in the datasheet. Yes, that datasheet packed with number, figures, tables, graphs, slogans, marketing statements, order numbers… you know right where to look, don’t you?
Hackaday has you covered on this one. In under 10 minutes [Bil Herd] will not only show how easy these calculations are, he’ll tell you where to look in the datasheets to get the info you need quickly.
Continue reading “Hot or Not? Find Out How to Calculate Component Heat and Why You Should”
[Dale Botkin], [N0XAS], is a competent designer for the amateur radio crowd and has a part-time business on the side selling a few kits. As anyone who owns a business, works in retail, or simply interacts with the general population will know, eventually you’ll have to deal with one of those customers. [Dale]’s latest horror story (here’s the coral cache but that doesn’t seem to be working either) comes from someone who bought a little repeater controller. You’re looking at this customer’s handiwork above. It gets worse.
After this customer completely botched an assembly job, he contacted [Dale] for some technical assistance. [Dale] graciously accepted a return and received the above mess of solder, wires, and parts. Then an email disputing the Paypal charge arrived. The customer wanted a refund for the original kit and the cost of shipping it back.
Oh, but it gets better. After posting this story, [Dale] received yet another email from an FBI agent demanding that his original post be taken down. The email from the FBI came from a Czech domain, so of course this is a totally legit demand.
So there’s your, “worst customer ever” story from the world of kit electronics. The assembly is impressively bad, even for something that was ‘professionally installed by an electrician’, but mail fraud and impersonating federal officials just takes this over the top.
Quick note: any doxxing in the comments will be deleted, so just don’t do it.
[James] needed some cool transportation for the upcoming Easter Camp in New Zealand, so he created a custom motorized shopping trolley that is sure to turn heads. The base of this project is a standard mobility scooter, which conveniently has a modular design. All of the electronics have connectors for quick service and the entire rear axle and motor assembly pop off with the pull of a lever.
[James] had to do a bit of welding and chassis rework to achieve his goal of mounting a shopping cart top to the scooter’s frame. Once finished, though, the setup looked great. It was actually comfortable to sit in, as [James] made a cutout for the driver’s feet to pass through. The real fun came with the electronics. The trolley is the most wired mobility scooter mod we’ve ever seen. Most of the electronics are contained in a project box under the seat, with several Arduinos that control the various systems: interfacing with the original scooter electronics, a GPS receiver, and a GSM radio. [James] also went as far as to add RGB LED headlights, a horn, and a multi-tone siren from Jaycar.
Driving the trolley is simple. An arcade joystick selects the speed, and the scooter’s standard hand controls are used for forward, reverse, and steering. One of the more interesting mods [James] made was a custom Windows app to control the trolley via a USB radio module. The entire system can be secured, with the security code stored in NVRAM to prevent a power cycle from unlocking the system. [James] can even command the trolley to go forward or reverse from his touch screen. We’d love to see him add a steering servo to make it a completely remote-controlled solution, though this step would require some sort of clutch for manual control.
The final design works very well. [James] may not win any drag races by keeping scooter’s original speed controls and associated electronics, but he did extend the range with larger batteries, so we’re sure the trolley will be a hit all over the camp. Similar projects have been built using the base of an electric wheelchair. If you have one that you want to control without invasive changes to the hardware, check out this accessibility hack which interfaces using a connector.
Continue reading “Shopping Trolley is Wired for Camp”
In reaction to the other air gap flash unit we featured a few days ago, [Eirik] sent us a tip about another one he recently made. In his setup, the duration of the flash peak intensity is around 300ns (1/3,333,333 of a second). As a reminder, an air flash unit consists of a circuit charging a high voltage capacitor, a circuit triggering a discharge on demand, a high voltage capacitor and the air flash tube itself. The flash tube contains two wires which are separated just enough to not spark over at max potential. Isolated from the other two, a third wire is placed in the tube. This wire is connected to a trigger/pulse transformer, which will ionize the gap between the two capacitor leads. This causes the gap to breakdown and a spark to form, thereby creating a flash of light.
[Eirik] constructed his flash tube using an olive jar and a glass test tube. As you can see from the (very nice) picture above, the spark travels along the glass test tube, making the quenching much faster than in an open air spark. [Eirik] built his own high voltage capacitor, using seven rolled capacitors of roughly 2nF each made with duct-tape, tin foil and overhead transparencies. For ‘safety’ they are stored in a PP-pipe. A look at the schematics and overall circuit shown on the website reveals how skilled [Eirik] is, making us think that this is more a nice creation than a hack.
Disclaimer: As with the previous airgap flash, high voltages are used here, so don’t do this at home.