Year: 2007

Hackit: FRS/GMRS Portable Radios

November 18, 2007 by 98 Comments


FRS and GMRS radios have the performance that we wished walkie talkies had when we were kids. I find them interesting because they aren’t quite as tied down as amateur radio bands. (They’re freaking cheap and you can give them to unlicensed users.) I’ve been surprised by the lack of hacks for these little guys. Garmin married them with a GPS unit to create a sort of hand held APRS device called the Rhino. Since I’ve got a couple of kids, I’m thinking that smacking a GPS into one of these little wrist radios with a modified opentracker (PIC based APRS encoder) would be great for tracking the family on hikes and ski/snowboard trips.

The response to Hackit has been fantastic! Each week I’m going to bring up some hardware. You guys get to pick your brains and suggest new, interesting projects. Look for a round-up and bounty post in the next week or so.

So, got a better idea? Let’s hear it!

Spread Spectrum Freq Hopping USB RF Modem

November 17, 2007 by 17 Comments


Since I mentioned Sparkfun electronics in the parts finding how-to, I started poking around their forums and stumbled across this interesting USB RF modem. It uses an off the shelf Semtec DP1205 RF module that’s controlled by a PIC 18F2550. The really interesting thing is that it uses spread spectrum frequency hopping – which means that by FCC rules, it can transmit up to 1 watt at 900Mhz.

Friday Night Pyro Extra

November 16, 2007 by 6 Comments


Well, not quite so much a pyro, but this setup rocks for cooking some good steaks.

[Tony] sent in this mp3 doorbell hack. I’m thinking… Star Wars theme song.

[Joey] let me know about this odd hack that adds guitar foot pedals to every button on a gameboy. (It makes sense if you remember that they’re popular for 8-bit sound production)
[Chris] sent in his wooden robot arm. It’s a simple servo based design, but it might be a good place to start if you’re leaning in that direction.

This already got plenty of attention, but [Billy] took his iPod apart and encased it in a block of resin. It’s still works, via a dock cable.

[D.G.] sent in this cheap ring-light tutorial. It’s based on a cheap LED light that’s got a set of ring mounted LEDs from the factory.

[Eliot] noted this interesting take on finding slingboxes using geographical IP addresses to set up your target search.

Finally, if you enjoyed [Eliot]’s visit to [Mr. Jalopy]’s garage, you might want to check out the video version on BoingBoingTV.

How-To: Where To Find Parts For Your Projects

November 16, 2007 by 78 Comments


Hunting down the right parts usually takes more time than soldering everything together. I can’t count the number of projects that I tried to build and couldn’t find some key component that’s no longer made. You can help put together a list of suppliers at the end, but the idea is to have a quick reference to get your projects rolling (saving your money for important things, like espresso). Even if you’re familiar with the usual electronics parts shops, chime in to help me create a list of the best suppliers to fuel those hardware hacking projects.

Continue reading “How-To: Where To Find Parts For Your Projects” →

Automatic Projector Calibration

November 15, 2007 by 40 Comments


[Johny Lee] sent in his(pdf) awesome projector calibration project. By adding embedding some optical fiber that feed into a set of USB connected light sensors, his groups software can determine the exact pixel position of each sensor. Once the positions are determined, the projected image can be dynamically adjusted to fix the screen. The technique can be used to stitch together multiple projectors, and even calibrate an image to project onto a three dimensional model. I know some home theater nuts that would love to have this system for calibrating their CRT projectors.

This is such an excellent project, that I want to give credit where it’s due – it was developed by [Johnny C. Lee], [Paul H. Dietz], [Dan Maynes-Aminzade], [Ramesh Raskar] and [Scott E. Hudson].

Be sure to check out the video demo after the break!

Continue reading “Automatic Projector Calibration” →

Toilet Terror Level Indicator

November 14, 2007 by 11 Comments


Normally, this wouldn’t quite make my radar, but [sprite_tm] built it, and it’s funny as hell. He created a Terror Level indicator for… his toilet. Rather than create an exotic smell detector, he simply uses a photo diode to measure the amount of time that the light has been on in the ol’ water closet. As time progresses, so does the Terror Level indicator. To make an audible indicator, he used the PWM generator in the ATTiny231to create a sort of ping sound when the level escalates. (I can definitely think of someone I need one of these things for.)