Brute Forcing Passwords With A 3D Printer

December 15, 2017 by Adam Fabio 17 Comments

Many of us use a 4 digit pin code to lock our phones. [David Randolph] over at Hak5 has come up a simple way to use a 3D printer to brute force these passwords. Just about every 3D printer out there speaks the same language, G-code. The same language used in CAD and CNC machines for decades.

[David] placed a numeric keypad on the bed of his printer. He then mapped out the height and positions of each key. Once he knew the absolute positions of the keys, it was easy to tell the printer to move to a key, then press and release. He even created a G-code file which would press every one of the 10,000 4 key pin combinations.

A file this large was a bit unwieldy though, so [David] also created a python script which will do the same thing — outputting the G-code and coordinates to brute force any 4 pin keypad. While a printer is quite a bit slower than Hak5’s own USB Rubber Ducky device (which acts as an automated keyboard), it will successfully brute force a password. Although most phones these days do limit the number of password attempts a user gets.

[David] admits this is probably useless in a clandestine/hacking application, but the video is still a great introduction to G-code and using 3D printers for non-printing functions.

Continue reading “Brute Forcing Passwords With A 3D Printer” →

AsciiCam: Make ASCII Art With Your Phone

November 25, 2017 by Adam Fabio 10 Comments

We admit it, we have a nostalgic soft spot for ASCII Art. Pictures made form characters, printed on an old-fashioned line printer. They’ve been a hacker standby since the 1960’s. Times have moved on though. These days we’re all carrying supercomputers in our pockets. Why not use them to create more great ASCII art? That’s exactly what [Brian Nenninger] did with AsciiCam. AsciiCam lets you use your Android phone’s camera to create ASCII images.

Using the software is simple. Just launch it and you’re greeted with an ASCII preview of the camera image. Users can select from a 16 color palette and full 24 bit color. Monochrome modes are also available. You can also choose from black text on a white background or white text on black.

The great thing about AsciiCam is the fact that it is open source. You can download the full source code from Github. If you just want to run the software, it’s available through the Google Play Store. This is a labor of love. The first Github commits were six years ago, and [Bran] is still working — the most recent commits were made only a few days back. AsciiCam is also a good example for neophyte Android programmers.

Want to know more about ASCII art? Check out Al’s history of ASCII art, or this talk about both ASCII and ANSI creations.

This Power Strip Is A Fire Starter

October 27, 2017 by Adam Fabio 112 Comments

A few weeks ago I needed a power strip in my home office. The outlet in question is located behind a filing cabinet so it would need a low profile plug. I jumped on Amazon to buy a surge suppressor strip. That’s when I noticed strips with rotating plugs. I’ve always had some apprehensions about plugs like that, though I could never quite put my finger on why. Looking at the reviews on this particular plug, I found some scary issues. Photos of melted plugs, melted outlets, and cries of “fire hazard”. So I did what any crazy hacker would do – bought two power strips. One with a fixed right angle plug to use in my office, and one with a rotating plug to tear down.

Surge suppressors, power strips, outlet strips, they have many names. Underwriter’s Laboratories (UL) calls them “Relocatable power taps”. They all have several outlets, most have a circuit breaker of some sort inside, and some have circuits for surge suppression. These are some of the most common devices to find in the modern home. Many of our houses were designed and built before surround sound, cable boxes, computers, modems, cell phone chargers, tablet chargers, and all our other modern conveniences. There weren’t as many electrical loads, so the houses didn’t have many outlets. Power strips solve this problem.

After a couple of days, I had my strips in hand. I expected the plug to rotate once – maybe 270 degrees. That would indicate there were wires connecting the rotating head to rest of the plug. Not so – this plug would spin round and round all day long.

Continue reading “This Power Strip Is A Fire Starter” →

Rescuing An Antique Saw Set

October 18, 2017 by Adam Fabio 16 Comments

Who doesn’t like old tools? Even if they aren’t practical to use for production, plenty of old tools still have a life to offer the hobbyist or home worker. Some tools might seem a bit too far gone – due to age, rust, or practicality, to use. That’s where [Hand Tool Rescue] comes in. [HTR] finds rusty, dirty old tools, and brings them back to life. Sometimes they’re practical tools, other times, they’re a bit out there. In a recent video, he restored a BeMaCo automatic saw set from the 1940’s. Saw sets are tools which bend each tooth of a saw blade slightly. Typically they are pliers-like devices.

The slight bend of each tooth on the blade widens the saw’s kerf and prevents binding. Typically these tools are pliers-like devices. The BeMaCo set is something else — it pulls the blade through tooth by tooth, while a spring-loaded head pecks away, bending each tooth. It’s something Rube Goldberg would have loved.

[HTR’s] filming style borrows a lot from [Jimmy DiResta], who we’ve covered here before. There are no words, and most of the video is sped up. Even with the fast video, [HTR] probably has many hours of footage to pare down to a 20-minute video.

The restoration begins with tearing the saw set apart. Every nut and bolt is removed. All the parts are cleaned, chemically de-rusted, and wire-wheeled. Even the motor is torn down, cleaned, and wired up. Then come the re-assembly. [HTR] gets every piece back in its proper place. We’re wondering how many times he had to refer to the teardown video to get everything right. Finally, the saw set is complete — ready for another 70 years of work.

The Early Bird Repairs A Slug

October 13, 2017 by Adam Fabio 12 Comments

When faced with a problematic Bird slug, [Robert Meister] didn’t give up. He pecked away at the slug and brought us all along for the ride. If that sentence didn’t make sense to you, read on!

Anyone who’s been to a hamfest has seen a Bird meter. The Bird Model 43 watt meter is the defacto standard for measuring transmitter power in-line. Bird meters don’t just work from DC to light though. In fact, the model 43 itself is just a bit of transmission line and a meter movement. The magic happens inside the swappable measurement element. These elements, affectionately called “slugs” are calibrated for a frequency band and power range. An example would be the model 4410-6, which works from 50 – 200 MHz, at up to 1 kW. Most hams have a collection of these slugs to go with the bands they transmit on.

[Robert]’s problem child was a model 100E element, good for 100 watts on 400 – 1000 MHz. The meter output seemed erratic though. A bit of troubleshooting with a second meter and a known good slug isolated the problem to the 100E. The problem was isolated to the slug, but how to fix it?

Slugs are sealed brass containers, each of which is calibrated to 5% accuracy at the factory. They are the closest thing you’ll find in the ham world to “no user serviceable parts inside”. Still, [Robert] had nothing to lose. He soaked the slug in a bit of Xylene solvent to loosen the glue holding the metal label on. Behind that were a painted screw and a hole for a calibration pot. We’re guessing the paint is Bird’s idea of tamper detection.

Pulling the screw out, and removing the nylon cover on the back of the slug revealed the real story. The slug contained a calibrated sensing loop, a diode, the calibration pot, and a terminating resistor. In [Robert]’s case, all he had to do was clean the contacts on the slug, and things worked fine.

For 11 years, anyway. After that, the slug started acting up again. Cleaning didn’t fix the problem this time. [Robert] ended up replacing the calibration potentiometer with a similar model from Digi-key. He re-calibrated the slug against his known good meter. It may not be a lab quality calibration, but this slug should be good for another few decades in his shack.

Cuban Embassy Attacks And The Microwave Auditory Effect

September 25, 2017 by Adam Fabio 323 Comments

If you’ve been paying attention to the news, you may have seen a series of articles coming out about US staffers in Cuba. It seems that 21 staffers have suffered a bizarre array of injuries ranging from hearing loss to dizziness to concussion-like traumatic brain injuries. Some staffers have reported hearing incapacitating sounds in the embassy and in their hotel rooms. The reports range from clicking to grinding, humming, or even blaring sounds. One staffer described being awoken to a horrifically loud sound, only to have it disappear as soon as he moved away from his bed. When he got back into bed, the mysterious sound came back.

Cuba has denied any wrongdoing. However, the US has already started to take action – expelling two Cuban diplomats from the US in May. The question though is what exactly could have caused these injuries. The press has gone wild with theories of sonic weaponry, hidden bugs, and electronic devices, poisons, you name it. Even Julian Assange has weighed in, stating “The diversity of symptoms suggests that this is a pathogen combined with paranoia in an isolated diplomatic corps.”

So what’s going on? Bizarre accidents? Cloak and dagger gone awry? Mass hysteria among the US state department, or something else entirely? Continue reading “Cuban Embassy Attacks And The Microwave Auditory Effect” →

Reviving A $25 Generator

September 22, 2017 by Adam Fabio 35 Comments

[Jennies Garage] found a used and abused inverter based generator in the clearance section of his local home improvement store. The generator had been returned on a warranty claim and was deemed uneconomical to fix. Originally $799, [Jennies Garage] picked it up for just $25. He documented his quest to get the device running with a trio of videos.

The generator had spark, but didn’t want to fire. The only obvious problem was the fact that the machine had been overfilled with oil. There was little or no compression, but that is not uncommon with modern small engines – many of them have a compression release mechanism which makes them easier to start.

With all the obvious problems eliminated, the only thing left to do was tear into the engine and figure out what was wrong. Sure enough, it was a compression issue. The overfull oil condition had forced engine oil up around the piston rings, causing them to stick, and snapping one of the rings. The cylinder bore was still in good shape though, so all the engine needed was a new set of rings.

That’s when the problems started. At first, the manufacturer couldn’t find the rings in their computer system. Then they found them but the rings would take two weeks to ship. [Jennies Garage] isn’t the patient type though. He looked up the piston manufacturer in China. They would be happy to ship him complete pistons – but the minimum order quantity was 5000. Then he started cross-referencing pistons from other engines and found a close match from a 1960’s era 90cc motorcycle. Ironically, it’s easier to obtain piston rings for an old motorcycle than it is to find them for a late model generator.

The Honda rings weren’t perfect – the two compression rings needed to be ground down about 1/2 a millimeter. The oil ring was a bit too thick, but thankfully the original oil ring was still in good shape.

Once the frankenpiston was assembled, it was time to put the repair to the test. [Jennies Garage] reassembled the generator, guessing at the torque specs he didn’t have. The surgery was a complete success. The generator ran perfectly, and lit up the night at the [Jennies Garage] cabin.

If you’re low on gas, no problem. Did you know you can run a generator on soda? Want to keep an eye on your remote generator? Check out this generator monitor project.

Continue reading “Reviving A $25 Generator” →