A Nokia Shield For The Arduino

The Nokia 3100 is a classic in the circles we frequent. The LCD in this phone is a very cheap and very common display, and it was one of the most popular phones since the phone from Bell, making it a very popular source of cool components.

Now everything is an Internet of Thing, and cellular data for microcontroller projects is all the rage. [Charles] thought it would be interesting to use the famous Nokia 3100 to transmit and receive data. After battling with some weird connectors, he succeeded.

The Nokia 3100 doesn’t have a USB connector, as this phone was made before the EU saved us from a menagerie of cell phone chargers. Instead, this phone has a Nokia Pop-Port, a complex connector that still has TX and RX pins running at 115,200 bit/s 8N1. By fitting a USB socket onto a prototyping board, adding a few level shifters, and connecting the pins in the right order, [Charles] was able to get his Arduino talking to an old Nokia Brick.

[Charles] isn’t quite at the level of sending SMS from his confabulation, and even following a tutorial from [Ilias Giechaskiel] didn’t work. [Charles] is looking for help here, and if you have any suggestions, your input would be appreciated.

There is a problem with using a Nokia 3100 as a cheap Arduino cellular shield: it’s only 2G, and sometime soon those cell towers will be shut down. For now, though, it works, and once those 2G towers are shut down, there are plenty of options with cheap, early Android and iOS phones.

Interactive Robot: Project Naughty Ball

A month before the Bay Area Maker Faire, there were ominous predictions the entire faire would be filled with BB-8 droids, the cute astromech ball bot we’ll be seeing more of when The Force Awakens this December. This prediction proved to be premature. There were plenty of R2 units droiding around the faire, but not a single BB-8. Perhaps at the NYC Maker Faire this September.

skeletonRegarding ball bots, we did have one friendly rolling companion at Maker Faire this year. It was a project by UC Davis students [Henjiu Kang], [Yi Lu], and [Yunan Song] that rolls around, seeking out whoever is wearing an infrared ankle strap. They team is calling it Project Naughty Ball, but we’re going to call it the first step towards a miniature BB-8 droid.

The design of the Naughty Ball is somewhat ingenious; it’s set up as a two-wheel balancing bot inside a clear plasic sphere. A ton of batteries work well enough as the ballast, stepper motors and machined plastic wheels balance and steer the ball bot, and the structure on the top hemisphere of the ball houses all the interesting electronics.

There is a BeagleBone Black with WiFi adapter, a few motor drivers, an IMU, and a very interesting 3D printed mount that spins the robot’s eyes – infrared cameras that spin around inside the ball and track whoever is wearing that IR transmitting ankle band.

As far as robotics project go, you really can’t do better at Maker Faire than a semi-autonomous ball bot that follows its owner, and the amount of work these guys have put into this project sends it to the next level. You can check out a video description of their project below.

Build A 100W LED Flashlight

In case you’re not aware, you can hop on your favorite online Chinese electronics retailer and buy a hundred Watt LED module for less than $10 USD. That’s an enormous amount of retina-burning fun, but how do you turn it into a flashlight? DIY Perks shows you how.

The main issue when dealing with these large LED modules is heat. Even though there’s many times more efficient than incandescent bulbs per Watt, that’s still an incredible amount of heat that needs to be removed. There’s a piece of equipment you might have sitting around that does just that: the lowly CPU cooler.

If the CPU heatsink and fan are big enough, the LED module can be attached right to the bottom. With a DC to DC boost converter modified so the entire flashlight can be powered from a LiPo cell, this unit is completely portable, ready to take camping, or even for some very interesting videography.

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Hackaday Prize Entry: The MultiSpork

If you’re working on a mobile project – a robot, something outside, or even your car – you don’t want to bring an oscilloscope, logic analyzer, signal generator, or any other piece of equipment that should stay on the bench. For his Hackaday Prize Entry, [Pierce Nichols] is working on the electronic equivalent of a Leatherman: something small and portable that also does just enough to get by in a pinch.

The MultiSpork, as [Pierce] calls his device, is a single WiFi enabled board that’s completely portable. With the addition of a $50 Android tablet, it’s very close to a complete electronics lab in a box.

The heart of the MultiSpork is a new chip from Maxim, the MAX 11300. This chip has 20 pins that can be used as a 12-bit ADC, a 12-bit DAC, or as GPIOs. it’s a logic analyzer, signal generator, oscilloscope, and a Bus Pirate in a single chip. As far as the rest of the board goes, [Pierce] is forgoing any notion of a hardware freeze and changing the Atmel microcontroller over to a TI CC3200 chip that will be coming out soon.

[Pierce] put together a short video describing the MultiSpork; you can check that out below.


The 2015 Hackaday Prize is sponsored by:

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How To Tell If You’re Installing Foil Capacitors Backwards

It only takes one mistake to realize electrolytic capacitors have a polarity, but if you’re working with old tube gear, tube amps, or any old equipment with those old orange dip, brown dip, or green dip foil capacitors you also have to watch your polarity. These old caps were constructed with a foil shielding, and there’s always one side of these caps that should always be connected to the chassis ground. If you don’t, you’re going to get interference – not something you want in an amplifier circuit.

Old caps that have long since given up the ghost usually have a black band designating whatever side of the cap the ‘foil ground’ is. This is the side that should be connected to ground. If you look at modern foil caps, you might also see a black band on one side of the cap, which should – if we lived in a just world – also designate the foil ground. This is not always the case.

To properly test foil caps and determine which side should be closer to ground, you can construct a small tester box that’s more or less an h-bridge with a single switch and a pair of alligator clips in the middle. Connect the cap to the clips, put the output of the circuit in your scope, and flick the switch: the direction that has the least amount of interference is the denotes the foil ground of the cap. Replace those old caps in your vintage equipment with a new, correctly oriented cap, and you’re well on your way to having a great sounding amplifier.

Video below.

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A Very, Very Small IMU

The reason we’re playing with quadcopters, flight controllers, motion controlled toys, and hundreds of other doodads is the MEMS revolution. A lot is possible with tiny accelerometers and gyroscopes, and this is looking like the smallest IMU yet. It’s an 18mm diameter IMU, with RF networking, C/C++ libraries, and a 48MHz ARM microcontroller – perfect for the smallest, most capable quadcopter we’ve ever seen.

The build started off as an extension of the IMUduino, an extremely small rectangular board that’s based on the ATMega32u4. While the IMUduino would be great for tracking position and orientation over Bluetooth, it’s still 4cm small. The Femtoduino cuts this down to an 18mm circle, just about the right size to stuff in a model rocket or plane.

Right now, femtoIO is running a very reasonable Kickstarter for the beta editions of these boards with a $500 goal. The boards themselves are a little pricey, but that’s what you get with 9-DOF IMUs and altimeter/temperature sensors.

Tearing Down The Apple Watch

The Apple Watch has been out for nearly a month now, but so far we haven’t seen a good look at the guts of this little metal bauble of electronic jewelry. Lucky for us that a company in China is hard at work poking around inside the Apple Watch and putting up a few incredible SEM images along the way (Google Translatrix).

This isn’t the first Apple Watch teardown that’s hit the intertubes – iFixit tore one apart with spudgers and tiny screwdrivers and found someone skilled in the ways of tiny parts could probably replace the battery in this watch. Shocking for an Apple product, really. iFixit also took a look at the watch with an x-ray, revealing a little bit of the high-level design of the Apple Watch, the Apple S1 computer on a chip, and how all the sensors inside this wearable work.

A side view of a 6-DOF IMU
A side view of a 6-DOF IMU

This teardown uses an incredible amount of very high-tech equipment to peer inside the Apple Watch. Because of this, it’s probably one of the best examples of showing how these tiny sensors actually work. With some very cool images, a 6-DOF IMU is revealed and the Knowles MEMS microphone is shown to be a relatively simple, if very small part.

Now the Apple S1, the tiny 26.15mm x 28.50mm computer on a chip, serves as the brains of the Apple Watch. It’s breathtakingly thin, only 1.16mm, but still handles all the processing in the device.

Even if you won’t be buying this electronic accessory, you’ve got to respect the amazing amount of engineering that went into this tiny metal bauble of semiconductors and sensors.