Simple PCB Etchant Made From Chemicals You Can Put In Your Mouth

March 3, 2011 by Mike Nathan 68 Comments

etching_test

[Stephen] often finds the need to make his own PCBs at home, and when he got the urge to do some etching recently, he realized that he was fresh out of “Ferret Chloride and Bureaucratic Acid*.” Undeterred by his empty chemical cabinet, he poked around in his kitchen mixing together anything and everything that might have the ability to strip copper from a PCB.

Now, we don’t necessarily recommend this course of action, but it seems that he finally hit upon a winner. He discovered a formula that can be made at home from simple and safe household ingredients which does the job quite nicely. A fair warning however, standard ferric chloride disposal procedures need to be followed when using this solution.

If you want to know what he concocted in his kitchen as well as the chemistry behind it, you will have to visit his site, we won’t ruin it for you. You can however, see the solution at work in the video we have posted below.

*His joke, not ours

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Jittering Hexapod Dances To The Strokes Of Your Bluetooth Keyboard

March 3, 2011 by Mike Szczys 4 Comments

Here’s a small but functional hexapod that is controlled via Bluetooth. [Sigfpe] started with the hexapod kit sold by Polulu and added a BlueSMiRF modem to get the little guy’s communications up and running. But since the bot is merely three servos, a microcontroller board, sensors, and miscellaneous parts it’s an easy build for most electronic hobbyists.

Check out the video after the break to see the delightful dance it can perform at your bidding. When we first looked at the project we thought that the keyboard was directly paired with the bot for control, but a look at the code makes us think the computer is controlling it after processing keystrokes. Either way the BlueSMiRF should have no problem pairing with other Bluetooth devices so it’s just a matter of coding to get it taking commands from your device of choice. We’d love to see Android control but for the really hard-core code monkeys we think this should be voice controlled with a Bluetooth headset.

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Arduino Based Ambient Lighting Improvements

March 3, 2011 by Mike Szczys 12 Comments

[Simon] improved upon an existing hack by making this Arduino ambient lighting system that has four different color regions. He was inspired by [Roy’s] processing-based setup which we saw a few weeks ago. That system used processing to determine the average color of the currently displayed image, then it displayed the color on a single RGB LED strip. [Simon] was thinking a little bit bigger.

He purchased a lighting strip that could be cut into different sections and then set out to develop his own software for multiple color regions. He had little or no experience with Processing so he went one abstraction layer lower and used Java to code his interface. It’s got a lot of nice settings where you can tweak how, when, and why colors are displayed. In the end he has four independently addressable color strip on the left, right, top-left, and top-right of the screen. The best part is that the Java suite he developed can be used on different platforms, having been already tested on Windows and Linux.

Keypad Input Scanning By A 555 Timer

March 3, 2011 by Mike Szczys 17 Comments

[R-B] designed a 555 timer circuit to scan a keypad. Keypads are common interfaces for small projects and require row and column scanning by a microcontroller. [R-B’s] setup allows you to reduce the number of pins used on the microcontroller to just two. One is an interrupt that is triggered when any of the buttons are pushed, the other reads the frequency from the 555 chip. Each button has its own resistance which alters the frequency of the 555. The microcontroller reads the frequency for 100ms using a timer. The number of timer overflows that occur during that period directly correspond to the button press (five overflows for the numeral 5, zero overflows for the numeral zero).

We usually debounce our button presses for 40 ms, this is more than twice that amount of time but still not a staggering difference. It does make us wonder if you will miss quick button presses? The only really way to know is to try this out yourself. Check out the video after the break and don’t forget to leave a comment with your own experiences in working with the circuit.

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Cutting Out Your Own Breakout Boards

March 3, 2011 by Mike Szczys 24 Comments

[Caleb] needed to use some surface mount components when prototyping. Instead of buy a breakout board he made one himself without doing any etching. The process he shows off in the video after the break uses copper tape to layout the traces for the board. It’s quite an interesting method which requires a sharp knife and a steady hand.

He used regular protoboard as a substrate and applied a layer of copper tape on the side without copper pads. From there he poked holes for the DIP pin headers. Now it’s time to do some cutting. [Caleb] removed the band of copper that would fall in between the pins of the surface mount device. He then tacked it in place with one dot of solder and drew the traces from the part to the pin headers. After removing the part he cut out the waste in between each line he drew with marker. What he’s left with is a set of thin traces that connect each pin of the surface mount component to the corresponding through-hole pin header.

This is very time-consuming, but then again so is soldering jumper wires to small-pitch components.

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DIY Ring Light Takes Its Cues From Fiber Optic Toys

March 3, 2011 by Mike Nathan 11 Comments

the_ram_ring_light

DIY ring light setups for DSLR cameras are nothing new around here. While most of them rely on an array of LEDs or a mirror-based light tube, [Wolf] had a different idea. He figured that since optical fibers are made specifically for transmitting light from one place to another, they would make a perfect medium for constructing a ring light.

Since he was using the camera’s built-in flash to power the ring light, he was able to provide a function that few other DIY ring lights do: proper flash compensation. Typically, a self-made ring light flashes at one set brightness, regardless of how much light is actually required to compose the image.

The construction was relatively simple, albeit time consuming. He procured a set of fiber optic cables that had been melted together into 150 small bundles, which he then glued to an acrylic ring that he fabricated. The end result isn’t the most aesthetically pleasing ring light we’ve ever seen, but it’s the pictures that matter at the end of the day. As you can see on his site, they speak for themselves.

Looking to build your own ring light? Check out a couple of other projects we have featured in the past.

Nintendo 3DS Teardown

March 3, 2011 by Chris Nelson 14 Comments

The Nintendo 3DS has been out for a couple days now (in japan) and the folks over at [tech on] were nice enough to do a teardown. Besides all the regular teardown goodies you can also get a good look at the 3DS’ 3D screen with a microscope. Turns out its a parallax barrier display which means that there are slits on top of the LED array to create a 3D effect without the use of special glasses. The rest of the hardware seems pretty standard, running an ARM based processor with some DRAM and NAND flash. Apparently the 3DS didn’t get much of an upgrade (downgrade?) as far as DRM is concerned because there are already examples of the 3DS running pirated games using a R4 card on youtube.

[via engaget]

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