Year: 2015

Scanning Electron Microscope Images And Animations Pulled By Impressive Teensy LC Setup

September 5, 2015 by 29 Comments

When you’ve got a scanning electron microscope sitting around, you’re going to find ways to push the awesome envelope. [Ben Krasnow] is upping his SEM game with a new rig to improve image capture (video link) and more easily create animated GIFs and videos.

The color scheme of the SEM housing gives away its 80s vintage, and the height of image capture technology back then was a Polaroid camera mounted over the instrument’s CRT. No other video output was provided, so [Ben] dug into the blueprints and probed around till he found the high-resolution slow scan signal.

To make his Teensy-LC happy, he used a few op-amps to condition the analog signal for the greatest resolution and split out the digital sync signals, which he fed into the analog and digital ports respectively. [Ben] then goes into a great deal of useful detail on how he got the video data encoded and sent over USB for frame capture and GIF generation. Reading the ADC quickly without jitter and balancing data collection with transmission were tricky, but he has established a rock-solid system for it.

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Slimline USB Charger For Tiny Ham Radios

September 5, 2015 by 12 Comments

The recent trend to smaller and smaller handy talkie (HT) transceivers is approaching the limits of the human interface. Sure, engineers could probably continue shrinking the Baofeng and Wouxun HTs further, but pretty soon they’ll just be too small to operate. And it’s getting to the point where the accessories, particularly the battery charging trays, are getting bulkier than the radios. With that in mind, [Mads Hobye] decided to slim down his backpacking loadout by designing a slimline USB charger for his Baofeng HT.

Lacking an external charging jack but sporting a 3.7 volt battery pack with exposed charging terminals on the rear, [Mads] cleverly capitalized on the belt clip to apply spring tension to a laser-cut acrylic plate. A pair of bolts makes contact with the charging terminals on the battery pack, and the attached USB cable allows him to connect to an off-the-shelf 3.7 volt LiPo USB charger, easy to come by in multicopter circles. YMMV – the Baofeng UV-5R dual-band HT sitting on my desk has a 7.4 volt battery pack, so I’d have to make some adjustments. But you have to applaud the simplicity of the build and its packability relative to the OEM charging setup.

This isn’t the first time we’ve seen [Mads] on Hackaday. He and the FabLab RUC crew were recently featured with their open-source robotic arm.

Orange Is The New ($15) Pi

September 5, 2015 by 105 Comments

When the Raspberry Pi came on the scene it was hard to imagine that you could get a fairly complete Linux system for such a low price. The Pi has gotten bigger, of course, but there are still a few things you miss when you try to put one into a project. Wifi, comes to mind, for example. The first thing you usually do is plug a Wifi dongle in, consuming one of the two USB ports.

The Orange Pi is a direct competitor and has a few variants. Originally, the board cost about $30 but sports WiFi, a 1.6 GHz processor, 8 GB of flash, and a SATA interface. There’s now a reduced version of the board for about $15 that deletes the flash and SATA along with the WiFi and one of the original’s 4 USB ports. Still, the Raspberry Pi doesn’t have built-in flash. And the $15 Orange Pi PC has the things you’d expect on a Pi (HDMI and Ethernet) along with other extras like an IR receiver and an on-board microphone. Not bad for $15 considering it has a quad-core processor, a GPU and 1GB of RAM. Continue reading “Orange Is The New ($15) Pi” →

Hackaday Prize Semifinalist: A Low Cost, DIY Fuel Cell

September 4, 2015 by 63 Comments

Electronic cars and planes are the wave of the future, or so we’re told, but if you do the math on power densities, the future looks bleak. Outside of nuclear power, you can’t beat the power density of liquid hydrocarbons, and batteries are terrible stores of energy. How then do we tap the potential of high density fuels while still being environmentally friendly? With [Lloyd]’s project for The Hackaday Prize, a low cost hydrogen fuel cell.

Traditionally, fuel cells have required expensive platinum electrodes to turn hydrogen and oxygen into steam and electricity. Recent advances in nanotechnology mean these electrodes may be able to be produced at a very low cost.

For his experiments, [Lloyd] is using sulfonated para-aramids – Kevlar cloth, really – for the proton carrier of the fuel cell. The active layer is made from asphaltenes, a waste product from tar sand extraction. Unlike platinum, the materials that go into this fuel cell are relatively inexpensive.

[Lloyd]’s fuel cell can fit in the palm of his hand, and is predicted to output 20A at 18V. That’s doesn’t include the tanks for supplying hydrogen or any of the other system ephemera, but it is an incredible amount of energy in a small package.

You can check out [Lloyd]’s video for the Hackaday Prize below.

The 2015 Hackaday Prize is sponsored by:

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RaspiDrums Uses Expensive Sensors

September 4, 2015 by 3 Comments

Piezoelectric sensors are great for monitoring mechanical impacts with a microcontroller. Whether you’re monitoring knocks on a door or watching a heartbeat, they are a cheap way to get the job done. They do have their downsides, though, so when [Jeremy] wanted to build an electronic drum set, he decided to use more expensive accelerometers to measure the percussive impacts instead.

Even though piezo sensors are cheap, they require a lot of work to get them working properly. The ADXL377 3-axis accelerometer that [Jeremy] found requires much less work, plus provides more reliable data due to a 1kHz low-pass filter at the output. In his setup, a Raspberry Pi handles all of the heavy lifting. An ADC on each drum sends data about each impact of the drum, and the Raspberry Pi outputs sound via the native Alsa driver and a USB sound card.

This project goes a long way to show how much simpler a project like this is once you find the right hardware for the job. [Jeremy]’s new electronic drums are very well documented as well if you are curious about using accelerometers on your newest project rather than piezo sensors. And, if you’re into drums be sure to see how you can have drums anywhere, or how you can build your own logic drums.

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Better TV Via Hacking

September 4, 2015 by 19 Comments

Smart TVs are just dumb TVs with a computer and a network connection, right? In a variation of rule 34, if it has a computer in it, someone will hack it. When [smarttvhacker] bought a Sony 48 inch smart TV, he noticed all the software licenses listed in the manual and realized that was a big leg up into hacking the TV.

We don’t have a comparable Sony model, but [smarttvhacker’s] post is a veritable travel log of his journey from TV viewer to TV ruler. By analyzing everything from network port scans to a dump of a firmware upgrade, he wound up being able to install a telnet server.

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Demonstrating Science At Harvard University

September 4, 2015 by 18 Comments

What if there was a job where you built, serviced, and prepared science demonstrations? This means showing off everything from principles of physics, to electronic theory, to chemistry and biology. Would you grab onto that job with both hands and never let go? That was my reaction when I met [Dan Rosenberg] who is a Science Lecture Demonstrator at Harvard University. He gave me a tour of the Science Center, as well as a behind the scenes look at some of the apparatus he works with and has built.

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