Apple 1 Emulator Is A Perfect Fit For Supercon Badge

November 13, 2018 by 9 Comments

Supercon badge hackers had to be ready to present their show-and-tell by 6 pm Sunday evening. This ruthless unmoving deadline meant every badge hack on stage represents an accomplishment in time management, and some luck, in addition to their own technical merits. But that deadline also meant a few fantastic projects lost their race against the clock. We were rooting for [Jac Goudsmit] to build an Apple I emulator as his badge expansion, but he wasn’t quite done when our badge hack ceremony began. After Supercon he went home, finished the project, and documented everything in a detailed writeup.

Our 2018 Supercon badge is built on a retro-computing theme, and the default firmware came with a BASIC interpreter as well as a Z80 emulator running CP/M. So an Apple 1 emulator should feel right home with its contemporaries. Mechanically speaking, all the parts were a tight fit on the badge expansion board given out to every attendee at Supercon. So tightly that [Jac] had to file down the two main chips in order to fit them side by side. The breadboard-like pattern of connected holes on the expansion board, intended to help ease in beginners for their badge hack soldering, proved to be an inconvenience in tightly packed arrangements such as this.

With all the work [Jac] had invested, it was heartbreaking to know he was only five minutes of soldering and 30 minutes of coding away when time ran out. Time pressure was part of the challenge faced by every Supercon badge hacker, and while we’re sad [Jac] missed the deadline for stage time we’re happy to see him finish and write it all up. We hope every badge hacker would write up their stories of frantic weekend projects. Those who do so on hackaday.io are encouraged to tag their project with “Supercon” and get them added to our list of badge hacks for everyone to admire.

FT8: Saving Ham Radio Or Killing It?

November 2, 2018 by 177 Comments

It is popular to blame new technology for killing things. The Internet killed newspapers. Video killed the radio star. Is FT8, a new digital technology, poised to kill off ham radio? The community seems evenly divided. In an online poll, 52% of people responding says FT8 is damaging ham radio.  But ham operator [K5SDR] has an excellent blog post about how he thinks FT8 is going to save ham radio instead.

If you already have an opinion, you have probably already raced down to the comments to share your thoughts. I’ll be honest, I think what we are seeing is a transformation of ham radio and like most transformations, it is probably both killing parts of ham radio and saving others. But if you are still here, let’s talk a little bit about what’s going on in ham radio right now and how it relates to the FT8 question. Oddly enough, our story starts with the strange lack of sunspots that we’ve been experiencing lately. Continue reading “FT8: Saving Ham Radio Or Killing It?” →

Decorative Light Box Lets You Guess The Time

October 19, 2018 by 7 Comments

Telling time by using the current position of the sun is nothing revolutionary — though it probably was quite the “life hack” back in ancient times, we can assume. On the other hand, showing time by using the current position of the sun is what inspired [Rich Nelson] to create the Day Cycle Clock, a color changing light box of the Philadelphia skyline, simulating a full day and night cycle in real time — servo-controlled sun and moon included.

At its core, the clock uses an Arduino with a real-time clock module, and the TimeLord library to determine the sunrise and sunset times, as well as the current moon phase, based on a given location. The sun and moon are displayed on a 1.44″ LCD which doubles as actual digital clock in case you need a more accurate time telling after all. [Rich] generally went out of his way with planning and attention to detail in this project, as you can see in the linked video, resulting in an impressively clean build surely worthy as gift to his brother. And if you want to build one for yourself, both the Arduino source code and all the mechanical parts are available on GitHub.

An interesting next iteration could be adding internet connectivity to get the current weather situation mixed into the light behavior — not that it would be the first time we’d see weather represented by light. And of course, simulating the northern lights is also always an option.

Continue reading “Decorative Light Box Lets You Guess The Time” →

The Bells! The Bells! One Battery Since 1840

October 7, 2018 by 18 Comments

It is good advice to change batteries in your fire alarms at least once a year. Even our low-power LCD calculators need new batteries from time to time. But at the University of Oxford, they have an electric bell that has been ringing essentially non-stop on one set of batteries for about 178 years! Is the energy crisis solved then? Perhaps not. The bells require a high voltage but very little current and the pair of batteries — piles in the parlance of 1840 — have kept the charge flowing for about 10 billion rings. As you can see in the video below, though, the ringing isn’t very vigorous.

How does it work? When you think of converting electrical power to mechanical motion you probably think of a motor, even though there are plenty of other transducers like speakers, muscle wires, and solenoids. Arguably the first device was electrostatic bells that were invented by a Scot named [Andrew Gordon] around 1742. [Ben Franklin] made them famous, though, so they are often called Franklin bells.

Continue reading “The Bells! The Bells! One Battery Since 1840” →

Robot Solves Rubik’s Cube With One Hand Tied Behind Its Back

October 3, 2018 by 3 Comments

For all those who have complained about Rubik’s Cube solving robots in the past by dismissing purpose-built rigs that hold the cube in a non-anthropomorphic manner: checkmate.

The video below shows not only that a robot can solve the classic puzzle with mechanical hands, but it can also do it with just one of them – and that with only three fingers. The [Yamakawa] lab at the University of Tokyo built the high-speed manipulator to explore the kinds of fine motions that humans perform without even thinking about them. Their hand, guided by a 500-fps machine vision system, uses two opposing fingers to grip the lower part of the cube while using the other finger to flick the top face of the cube counterclockwise. The entire cube can also be rotated on the vertical axis, or flipped 90° at a time. Piecing these moves together lets the hand solve the cube with impressive speed; extra points for the little, “How’s that, human?” flick at the end.

It might not be the fastest cube solver, or one that’s built right into the cube itself, but there’s something about the dexterity of this hand that we really appreciate.

Continue reading “Robot Solves Rubik’s Cube With One Hand Tied Behind Its Back” →

Trials And Tribulations In Sending Data With Wires

September 25, 2018 by 14 Comments

When working on a project that needs to send data from place to place the distances involved often dictate the method of sending. Are the two chunks of the system on one PCB? A “vanilla” communication protocol like i2c or SPI is probably fine unless there are more exotic requirements. Are the two components mechanically separated? Do they move around? Do they need to be far apart? Reconfigurable? A trendy answer might be to add Bluetooth Low Energy or WiFi to everything but that obviously comes with a set of costs and drawbacks. What about just using really long wires? [Pat] needed to connect six boards to a central node over distances of several feet and learned a few tricks in the process.

When connecting two nodes together via wires it seems like choosing a protocol and plugging everything in is all that’s required, right? [Pat]’s first set of learnings is about the problems that happen when you try that. It turns out that “long wire” is another way to spell “antenna”, and if you happen to be unlucky enough to catch a passing wave that particular property can fry pins on your micro.

Plus it turns out wires have resistance proportional to their length (who would have though!) so those sharp square clock signals turn into gently rolling hills. Even getting to the point where those rolling hills travel between the two devices requires driving drive the lines harder than the average micro can manage. The solution? A differential pair. Check out the post to learn about one way to do that.

It looks like [Pat] needed to add USB to this witches brew and ended up choosing a pretty strange part from FTDI, the Vinculum II. The VNC2 seemed like a great choice with a rich set of peripherals and two configurable USB Host/Peripheral controllers but it turned out to be a nightmare for development. [Pat]’s writeup of the related troubles is a fun and familiar read. The workaround for an incredible set of undocumented bad behaviors in the SPI peripheral was to add a thick layer of reliability related messaging on top of the physical communication layer. Check out the state machine for a taste, and the original post for a detailed description.

DrawBot Badge Represents The CNC World In Badge Design

September 16, 2018 by 13 Comments

Badges come in all shapes and sizes, but a badge that draws on a stack of Post-It notes is definitely a new one. The design uses three of the smallest, cheapest hobby servos reasonably available and has a drawing quality that creator [Bart Dring] describes as “adorably wiggly”. It all started when he decided that the CNC and mechanical design world needed to be better represented in the grassroots demo scene that is the badge world, and a small drawing machine that could be cheaply made from readily available components seemed just the ticket.

Two arms control the position of a pen, and a third motor lifts the assembly in order to raise or lower the pen to the drawing surface. Gravity does most of the work for pen pressure, so the badge needs to be hanging on a lanyard or on a tabletop in order to work. An ESP32 using [Bart]’s own port of Grbl does the work of motion control, and a small stack of Post-It notes serves as a writing surface. Without the 3D printed parts, [Bart] says the bill of materials clocks in somewhere under $12.

We’ve seen similar designs doing things like writing out the time with a UV LED, but a compact DrawBot on a badge is definitely a new twist and the fact that it creates a physical drawing that can be peeled off the stack also sets it apart from others in the badgelife scene.