RF Hacking: How-To Bypass Rolling Codes

March 6, 2016 by Brandon Dunson 19 Comments

The RF signal transmitted from a modern key fob and received by the associated vehicle is only used once. If the vehicle sees the same code again it rejects the command, however there is a loophole in those carefully chosen words. The code must be received by the vehicle’s computer before it can be added to the list of spent codes. [AndrewMohawk] goes through the process of intercepting a code sent from a key fob transmitter and preventing the vehicle from receiving it in a thorough post to his blog. You can see this attack working in his studio quality reenactment video after the break.

[Andrew] uses the YARD Stick One (YS1) which is a sub-GHz wireless tool that is controlled from a computer. The YS1 uses RfCat firmware, which is an interactive python shell that acts as the controller for the wireless transceiver.

This system is not without its problems: different frequencies are often used for different commands, [Andrew]’s scripts are designed to work with On-Off keying (OOK) leaving it useless when attacking a system that uses Frequency-Shift Keying (FSK). There is also the issue of rendering a target key fob non-functional but you’ll have to pop over to [Andrew]’s blog to read more about that.

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Offset Unicycle Built Mostly From A Single Bicycle

December 28, 2014 by Rick Osgood 32 Comments

[Lou’s] friends all said that it would be impossible to build a unicycle that had offset pedals. Moving the pedals to the front of the unicycle would throw off the balance and prevent the user from being able to ride it. [Lou] proved them wrong using mostly components from a single donor bicycle.

The donor bike gets chopped up into a much smaller version of itself. The pedals stay attached in the original location and end up being out in front of the rider. The seat is moved backwards, which is the key to this build. Having the rider’s legs out in front requires that there be a counter balance in back. Moving the seat backwards gets the job done with relative ease.

To prevent the hub from free wheeling, [Lou] lashes the sprocket directly to the wheel spokes using some baling wire. He also had to remove the derailer and shorted the chain. All of this gives the pedals a direct connection to the wheel, allowing for more control. The video does a great job explaining the build quickly and efficiently. It makes it look easy enough for anyone to try. Of course, actually riding the unicycle is a different matter. Continue reading “Offset Unicycle Built Mostly From A Single Bicycle” →

GuruBrew’s 15 Minute Windows 8 Survival Guide

September 30, 2013 by Todd Harrison 132 Comments

One thing very common to all of us is our reliance on operating systems in our hobby life. If that OS is Windows then you could be in for quite a shakeup with Windows 8. Many readers are Linux or Apple users and couldn’t care less if Microsoft is releasing an entire paradigm shift in desktop navigation. However, you just might find yourself facing this new OS and you’ll look like you’re on training wheels if you don’t get acquainted now, and considering the number of computers being released with Windows 8 its inevitable that day will come soon.

So if you haven’t been behind the wheel of Windows 8 then checkout [Steve’s] Windows 8 Survival Guide from the Guru Brew Tech Show. This is an excellent overview of the new touch screen navigation methods you’ll find in the Windows 8 desktop including hotspots, charms and tiles to name just a few. You’ll also learn tips to get around with a mouse and keyboard. It’s not a complete tutorial on using Windows 8 but you’ll at least know how to navigate, search for apps, work with multiple apps and find tools like task manager, control panel, file explorer as well as your familiar desktop.

Follow the break to watch the short survival guide video.

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How To Earn Your Hackaday Skill Badge

July 16, 2012 by Brian Benchoff 18 Comments

Since Adafruit released a few dozen hacker skill badges, we’ve been waiting for this tip to come in. [phillip torrone] over at Adafruit posted a requirement sheet put together by a school teacher-blogger friend aimed at high school students wanting to earn their Hackaday skill badge.

The requirement list is heavily influenced by the requirements needed to earn a merit badge in the Boy and Girl scouts – first, do a little research and be able to describe the type of build we usually feature. Then, describe the project to your teacher and directly relate your project to other builds featured on Hackaday. Solid advice, we have to say.

There’s a few solid tips that really help us out; putting up a blog post for your project really helps us out, as does hosting your code on a Git. Videos are always good, and even though I’m partial to Vimeo (these videos just come out looking more professional for some reason), a lot of our commentors prefer YouTube.

About the commentors: the requirement sheet specifically mentions ignoring the flame bait comments, something we’d have to agree with. The comments have gotten better, but the best way for you (yes, all of you) to help is just hit the report button and don’t feed the trolls.

If your post doesn’t make Hackaday, don’t feel bad. Before I started working here, I built a Mellotron and submitted it to the tip line. It didn’t get featured, but I just rolled with the punches. Now I’m waiting for a Raspberry Pi to come in so I can update that build and give it the rollout it deserves. If your build gets skipped, just re-submit a week or so later. We’re a fickle bunch and sometimes projects waste away in the tip line, especially if it’s similar to a recently posted build.

Tutorial: Build A Manifold Clock For $10

January 25, 2012 by Brian Benchoff 35 Comments

Every once in a while, the Hack a Day tip line gets a submission that is cool, but screams to be built in a few hours, possibly while consuming adult beverages. When [Shay] and [Ben] sent in their Manifold Clock Kickstarter, I knew what I had to do. To make a long story short, there’s a manifold clock hanging on my wall right now. Check out my manifold clock how-to guide after the break.

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Video Series Shows How To Build Your Own Solar-charged R/C Lawnmower

December 28, 2011 by Mike Nathan 18 Comments

rc-solar-lawnmower

As winter is officially upon us, we’re pretty sure that the last thing most of you are thinking about is mowing your lawn. We would argue that it’s actually the ideal time to do so – that is, if you are interested in automating the process a bit.

[Robert Smith] has spent a lot of time thinking about his lawn, wanting a way to sit back and relax while doing his weekly trimming. He set off for the workshop to build an R/C electric lawnmower, and thoroughly documented the process in order to help you do the same.

On his web site, you will find a series of videos detailing every bit of the solar charged R/C lawnmower’s construction, taking you through the planning phases all the way to completion. [Robert] has provided just about anything you could possibly need including parts lists, schematics, code, and more.

If the short introductory video below has you interested, be sure to swing by his site for everything you need to build one of your own.

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Papercraft Flowers Teach Kids About Batteries

May 12, 2011 by Mike Nathan 6 Comments

saltwater_papercraft_batteries

[Emily Daniels] has been teaching interactive electronics workshops geared towards children for some time now, recently holding a session that demonstrated how batteries work in a pretty novel fashion.

She wanted to keep things safe and simple due to the class size, so she didn’t want to rely on using soldering irons for the demonstration. Instead, she showed the children how batteries function by building simple voltaic cells with paper flowers, salt water, and LEDs. The paper flowers’ absorbency was used to act as a salt bridge between the wire pairs that adorned each petal. After salt water was applied to each of the flower’s petals, the center-mounted LED came to life, much to the amazement of her class.

The concept is quite simple, and the LED flowers are pretty easy to build, as you can see in her Instructables tutorial.

We think it’s a great way to demonstrate these sorts of simple concepts to kids, and hope to see more like it.

[via Adafruit blog]