Ever accidentally left your front door ajar and had a pet escape? [BlackCow] came up with a simple solution to this problem. The circuit is fairly rudimentary but a great example of using the basics to get the job done. Now, instead of having an alarm that sounds as soon as the door is open, he has a 30 second delay. This helps avoid the “boy who cried wolf” effect also known as the “vista security warning” effect of being bothered too many times for a non issue. We also have to say that we like his taste in blog layouts.…
About Caleb Kraft
Website: http://hackaday.com
Caleb Kraft has written 304 articles so far, you can find them below.
Hack
Time delay door alarm
Hack
Trashplane
[Flyboy258] shows us that hobby R/C airplanes can be built from trash relatively easily. A bit of old tarp and a simple frame work as the body. The rudder is made from old foam packaging. It seems to fly pretty well considering the lack of official design, or aerodynamic features.
[via Makezine]
Hack
C64 interface for your computer
Before we get started, lets just point out that this C64 was broken. He did not take a functional C64 out of operation for this. What he did do, was to build a hardware interface for for his VICE system. For those unfamiliar, VICE is a cross platform C64 emulator. [Simon] points out that the old games just weren’t as much fun without the original hardware. Having a broken C64 lying around, he put it to good use. It now acts as the interface for all the original fun stuff.
If you are a fan of the hardware, but…
Hack
Nook rooted without being opened
If you’ve got a nook, and wanted to get root privileges, but really didn’t want to open up your fancy new toy. We have good news. The people over at nookdevs have found that the nook looks for updates from the external microSD slot at boot time. Simply download the patch, load it and boot. Though it was previously possible to get root privileges before, you had to physically open the device. While we would have opened it anyway, we understand that there may be people who prefer not to.
Hack
Fix a projector on the cheap
[j] sent in this nice writeup on how to revive a dead projector. he managed to pick one up for $20 that had a broken bulb. While the prices of bulbs have come down considerably, they can still be a couple hundred dollars. Being resourceful, he decide to just use a halogen bulb that he picked up at his local big box shop. In the photos, he’s using a 50w mr16 bulb. The results really aren’t too bad. Especially considering that his cost for the entire project is now roughly $25. He does, however suggest that a 100 watt…
Hack
Home made panoramic camera
This one is from way back in 2002, but we didn’t see it till today. This is a hand built panoramic camera. The film is laid out across the back of the case, and when taking a picture, the lens assembly rotates to expose the film. It is a very nice looking design. The brass body is quite reminiscent of the recent one posted here. On the site, you’ll find not only the build log, but a full explanation of all the math behind the design. It is a very interesting read, even if you have no plans on…
Hack
Peggy2 x2, with video
Being avid fanatics of flashing lights, we always love to see the peggy2 in action. The video above shows another improvement, which is two peggy2 units working together as one. [iservice2000] chained the two together and wrote new code for the display. Using an Arduino to drive it all, he has gotten them to act as one. While video on the peggy2 isn’t new, this is the first time we’ve seen two of them chained together. The end result is going to be a scrolling sign that can be updated via the web, or that can display tweets. We…
Hack
Static Bleeder
When you are in the middle of the desert, pretty much every solution to a mechanical or electrical problem is a hack. [Sgt.M] who was deployed in Iraq sought out the help of radio guru [H.P. Friedrichs] about a static problem he was having. When dust storms would blow in strange things would happen in camp. Humming and crackling could be heard and [Sgt. M] actually had an electrical arc from a lamp to his had at a distance of about 2 feet.
[Friedrichs] helped him find the problem. Their antennae were acting as static electricity collectors in the…
Hack
[techknott]’s portable dreamcast
[Sydney] sent in this fantastic portable Dreamcast, built by [techknott], in response to the one we posted yesterday. While we agree, this one is much more polished, we want to point out why the post yesterday is more Hack A Day material. Sure, it looks more “hackish”, but that’s not what we are referring to. What we want to draw your attention to, is the lack of information. Yesterday, there was a build log. Today, there is not. Sure the other one could have had much much more information and we’re not commenting on which one is “better”. We’re…
Hack
Scan room, explore virtually
[Patrick] directed us to his project for alternate realism. The final goal is to be able to walk around in a space wearing a head mounted display, exploring a virtual representation of that space. This virtual representation could be altered, stylized, augmented and modified in countless ways. It is an exploration in perception, similar to enjoying different styles of painting, we could enjoy different styles of viewing a real space. Currently, it isn’t quite real time. He has to scan a room with a somewhat bulky device, then plug into his display to explore it. Being able to scan…
Game
Interactive beer pong table
Do you find that beer pong is too dull on its own to keep your attention? Do you require flashing lights to accentuate your imbibing? Here’s the perfect solution. Make an interactive beer pong table. It didn’t take much to sell us on the idea. We think everything needs a few more lights.
The idea is that as the game progresses, you get different feedback from the lights visible in the picture above. [rohitk] is using an Arduino and some pressure sensors to tell when each cup is removed. Based on this the LEDs change color.
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Make your own 3d monitor
Don’t let this cruddy video fool you. [Sprite_tm] has done an amazing job here. He has put together a fairly simple way of creating your own 3d monitor at home. The basic principle is easy to get. You have to supply different angles of an object, on the screen, at the same time. [Sprite_tm] has done this by using transparency sheets, printed with a pattern to only show specific pixels. As you move your head, you see a different set of pixels, and therefore a different image. It’s simple, but it works. The system isn’t really new. Traditional 3d…
