What Day Is It?

April 8, 2020 by 15 Comments

With much of the world staying at home at the moment, keeping track of our sanity and the day of the week is a bit of a challenge, especially without the normal daily routine to hold onto. To help with one of these problems, [phreakmonkey] has built a Day Clock. As the name suggests, it’s only purpose is to show what day of the week it is.

Avery simple device, the two main components are a servo and a Wemos D1 Mini, the popular ESP8266-based dev board. Using the NTPtimeESP library, it gets day of the week from the internet, and moves the servo to indicate the current day on a 3D printed face. Most readers should be able to whip one up in an hour or two, which can help keep sane in these interesting times.

For another Corona clock, check out [Elliot Williams]’ version that helps with keeping domestic peace. If you want to do something to combat the spread of the current epidemic, you can build a few face shields, make your idle computer available for Folding@Home or sew a few masks. Every bit helps.

On 5G And The Fear Of Radiation

April 8, 2020 by 178 Comments

The world around us is a scary place, with a lot of visible and invisible dangers. Some of those invisible dangers are pretty obvious, such as that of an electrical shock from exposed wiring. Some are less obvious, for example the dangers of UV radiation to one’s skin and eyes commonly known, but also heavily underestimated by many until it’s too late. In the US alone, skin cancer ends up affecting about one in every five people.

Perhaps ironically, while the danger from something like UV radiation is often underestimated, other types of electromagnetic radiation are heavily overestimated. All too often, the distinction between what is and isn’t considered to be harmful appears to be made purely on basis of whether it is ‘natural’ radiation or not. The Sun is ‘natural’, ergo UV radiation cannot be harmful, but the EM radiation from a microwave or 5G wireless transceiver is human-made, and therefore harmful. This is, of course, backwards.

Rather than dismissing such irrational fears of radiation, let’s have a look at both the science behind radiation and the way humans classify ‘danger’, such as in the case of 5G cell towers. Continue reading “On 5G And The Fear Of Radiation” →

A Hacker’s Guide To JTAG

April 8, 2020 by 6 Comments

If you’re reading Hackaday, you’ve almost certainly heard of JTAG. There’s an excellent chance you’ve even used it once or twice to reflash an unruly piece of hardware. But how well do you actually know JTAG? More specifically, do you know how useful it can be when reverse engineering hardware?

Whether you’re a JTAG veteran or a novice, this phenomenal guide written by [wrongbaud] is sure to teach you a thing or two. Starting with a low-level explanation of how the interface actually works, the guide takes you though discovering JTAG ports on unknown targets, the current state-of-the-art in open source tools to interact with the device, and finally shows a real-world example of pulling and analyzing a gadget’s firmware.

There’s no way to do his write-up justice with a breakdown or a summary, so we won’t even try. Just get comfortable, maybe grab a drink, and dive in. It’s certainly not a short read, but there isn’t a wasted word on the page. Every piece of the puzzle, from how to figure out an unlabeled pinout to determining the instruction length, is explained in exactly the amount of detail you’re looking for. This is a guide for hackers written by a hacker, and it shows.

It will probably come as no surprise to find this isn’t the first time [wrongbaud] has done a deep dive like this. Over the last few months we’ve been covering his series of practical reverse engineering guides, and each one has been an invaluable resource. Perfect study guides for when a global pandemic has you stuck in the house.

Industrial Robot Given New Life And Controller

April 8, 2020 by 9 Comments

We all think we could use a third arm from time to time, but when we actually play this thought experiment out in our heads we’ll eventually come to the same hurdle [caltadaniel] found, which is a lack of a controller. His third arm isn’t just an idea, though. It’s a Yaskawa industrial robot that he was able to source for pretty cheap, but it was missing a few parts that he’s been slowly replacing.

The robot arm came without a controller or software, but also without any schematics of any kind, so the first step was reverse engineering the wiring diagram to get an idea of what was going on inside the arm. From there some drivers were built for the servos, but the key to all of it is the homemade controller. The inverse kinematics math was done in Python and runs on an industrial PC. Once it was finally all put together [caltadaniel] had a functioning robotic arm for any task he could think of.

Interestingly enough, while he shows the robot brushing his teeth for him, he also set it up to flip the switch of a useless machine that exists only to turn itself off. There’s something surreal about a massive industrial-sized robotic arm being used to turn on a $20 device which will switch itself back off instantly, but the absurdity is worth a watch.

Continue reading “Industrial Robot Given New Life And Controller” →

Machine Vision Keeps Track Of Grubby Hands

April 7, 2020 by 4 Comments

Can you remember everything you’ve touched in a given day? If you’re being honest, the answer is, “Probably not.” We humans are a tactile species, with an outsized proportion of both our motor and sensory nerves sent directly to our hands. We interact with the world through our hands, and unfortunately that may mean inadvertently spreading disease.

[Nick Bild] has a potential solution: a machine-vision system called Deep Clean, which monitors a scene and records anything in it that has been touched. [Nick]’s system uses Jetson Xavier and a stereo camera to detect depth in a scene; he built his camera from a pair of Raspberry Pi cams and a Pi 3B+, but other depth cameras like a Kinect could probably do the job. The idea is to watch the scene for human hands — OpenPose is the tool he chose for that job — and correlate their depth in the scene with the depth of objects. Touch a doorknob or a light switch, and a marker is left on the scene. The idea would be that a cleaning crew would be able to look at the scene to determine which areas need extra attention. We can think of plenty of applications that extend beyond the current crisis, as the ability to map areas that have been touched seems to be generally useful.

[Nick] has been getting some mileage out of that Xavier lately — he’s used it to build an AI umpire and shades that help you find lost stuff. Who knows what else he’ll find to do with them during this time of confinement?

Continue reading “Machine Vision Keeps Track Of Grubby Hands” →

Learn PDP-11 Assembly For Fun But Probably No Profit

April 7, 2020 by 43 Comments

Learning a new skill is fun, especially one that could land you a new job. We don’t think you’ll find too much demand for PDP-11 assembly language programmers, but if it still interests you, check out [ChibiAkumas’s] video that starts a series on that subject for “absolute beginners.”

The PDP-11 is a venerable computer, but you can still find simulators ranging from SIMH to browser-based virtual devices with front panels. If you want real hardware, there is a PDP-11 on a chip that is still around (or you can score the real chips, sometimes) and there are some nice hardware simulations, too.

Continue reading “Learn PDP-11 Assembly For Fun But Probably No Profit” →

PCB Mill Turns Out Stylish Necklace

April 7, 2020 by 6 Comments

When needing a custom PCB, most of us will whip up design files and send them off to a board house. Prices are low and turnaround times are bearable, with quality that’s difficult to replicate at home. The old methods still have some value however, as [Bantam Tools] demonstrate with this attractive glowing hummingbird necklace.

The back side of the pendant neatly hides a button cell battery and a small SMD switch.

The necklace is made of copper-clad board, the type typically used by those who would etch their own PCBs at home. In this case, the board is placed on a [Bantam Tools] mill, which removes copper strategically and cuts out the final shape. This creates a series of traces on the back for a battery, LEDs and a small swtich, while creating areas on the other side of the board for light to shine through.

With a battery installed, the LEDs on the back side of the necklace glow through the fiberglass for a beautiful effect. With a PCB mill and a reflow oven, it’s remarkably easy to make, too. Of course, if you like your parts density a little higher, these FPGA earrings might be more your speed!