Building A Better Spectrum Analyzer For Radio Enthusiasts

February 8, 2011 by Mike Szczys 12 Comments

This spectrum analyzer project seeks to improve the quality of tools available to amateur radio operators. A lot of thought has gone into the design, and those details are shared in the verbose project log. The case was originally a CATV link transmitter, but most of the controls seen above have been added for this build, with unused holes filled and finished to achieve the clean look.

One noteworthy part of the build is the time that went into building a rather complicated-looking 1013.3 MHz cavity bandpass filter. Despite the effort, the filter didn’t work. Details are a bit sketchy but it seems that some additional tuning brought it within spec to complete that portion of the device.

This certainly makes other toy spectrum analyzers look like… toys.

[Thanks William]

Upvote/Downvote Cards

February 8, 2011 by Mike Szczys 11 Comments

Next time you throw together a talent show consider using these cards for up and down voting. [Frits Rincker] came up with the idea over the weekend based on the like and dislike buttons of Facebook. They consist of some foam board with LEDs in the outline of a hand. He built a switch which completes he blue circuit for the thumb’s up and a red circuit for thumb’s down by using a weight that slides freely in a channel, with a reed switch at either end. We’ve embedded the video after the break for you enjoyment.

Oh, and in case you were wondering; Hackaday likes this.

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Replace An N64’s Worn Out Joystick

February 8, 2011 by Mike Szczys 24 Comments

As gaming consoles age the controllers will inevitably show some wear, and sadly may give out all together. [Kyle] couldn’t bear to watch his Nintendo 64 controller bite the dust so he replaced the thumb stick with one from a PlayStation. This is a bigger job than you might imagine because the two parts are fundamentally different. The original N64 stick uses a rotary encoder to output data to the control chip, while the PlayStation stick is an analog device. [Kyle’s] solution was to read the analog values using a PIC, but lower in the thread you can read about another user who pulled off a similar hack using an AVR. Both convert the signals into the rotary encoder format that the N64 chip is listening for. From the looks of the clip embedded after the break, this couldn’t work any better!

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Fowl Accommodations Provided By Mathematics

February 7, 2011 by Mike Szczys 19 Comments

[Anthony’s] chickens happily return to roost each night thanks to the spacious house he built for them. Sadly the geodesic dome never became the home of the future despite what the people were promised. But using a bit of unorthodox joinery you can create enclosures for your chickens or other animals in need of shelter.

The construction begins with 30 isosceles triangles and nine equilateral triangles which he cut from solid wood on a chop saw. To join the pieces he used metal banding and screws, which hold the edges close together but allow them to flex. This solved the problem of precision mitres at the edge of each wood piece. Once the dome was fully assembled he filled the joints with caulk and finished it with rubber roofing compound.

Our only question is: how’s he going to automate the door of the coop?

Laptop LCD Reused In Beagleboard Project

February 7, 2011 by Mike Szczys 15 Comments

This daughterboard lets [Matt Evans] drive a laptop LCD using a Beagleboard. Apparently the Beagleboard gained a VGA header when it moved to revision C but [Matt’s] working with revision B4 which is why he had to do all of that ninja soldering with the blue wires. The driver board itself is a thing of beauty, hosting a DS90C363 LVDS serialiser as well as some buffer chips that handle level conversion for it. He’s also included an ATmega48 so that he has some options for future improvements.

The LCD is mounted in a custom acrylic case, with Beagleboard and driver board taped to the back of it. There’s RS232 and a USB hub which opens up the possibility of using a WiFi dongle for communications. So far he doesn’t have much functionality other than displaying images on the screen but there is some talk about using a touchpad for control. We’d love to see a touchscreen overlay, transforming the build into a proper ARM-based tablet.

A Charlieplex Display And A Board Layout Tip

February 7, 2011 by Mike Szczys 7 Comments

[Ben] is getting himself up to speed with microcontrollers. He jumped into the deep end by taking on this Charlieplex LED matrix build. As you can see after the break, he not only made the display work, but coded Conway’s game of life to run on the ATtiny85 that drives the device. What you see above is the prototype version that [Ben] used to make sure he had the hardware just right. He’s seeing the project through to a manufactured board and this is where the layout tip comes from. In order to make sure he had enough space for all of his components he printed out the board artwork, taped it to some Styrofoam, and then inserted all of the through-hole parts. Now he can be sure that physically the design works, we’ll keep our fingers crossed that everything is also kosher electrically.

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Sniffing RF Hardware Communication Packets

February 7, 2011 by Mike Szczys 7 Comments

[Travis Goodspeed] put together a proof of concept hack that sniffs wireless keyboard data packets. He’s using the Next HOPE badge that he designed as the hardware platform for these tests. It has an nRF24L01+ radio on-board which can easily communicate with 2.4 GHz devices.

The real trick comes in getting that radio to listen for all traffic, then to narrow that traffic down to just the device from which you want data. He covers the protocol that is used, and his method of getting around MAC address verification on the hardware. In the end he can listen to all keyboard data without the target’s knowledge, and believes that it is possible to inject data using just the hardware on the badge.