Hacking SPOT Personal Satellite Tracker To Pass More Information

October 1, 2011 by Mike Szczys 38 Comments

For less than $100 you can buy a little tracking module that will upload your location to a satellite. But you’ll only get latitude and longitude information. [Natrium42] spent some time reverse engineering the hardware, and the communications protocol, to allow custom data to be transferred using a SPOT module.

The flat fee for the hardware includes a one-year service plan allowing you to tack your device on the SPOT website. [Natrium42] started poking around in the transmitted data packages, and figured he could push custom messages like altitude data if he had some way to encode it as a valid latitude/longitude package. He found that location data is transmitted as two sets of three bytes each. The four least significant bits of each set get rounded by the server, leaving a total of 40 usable bits between the two data sets. He wrote encoding and decoding functions that will allow you to transfer whatever information you want.

So what is this good for? To get the process working he removed the MSP430 microcontroller from the board and is using his own replacement. So you can transmit GPS data from the onboard module, your own module, or sensor data for anything you’re able to hook up the to the replacement uC.

Make Your Own GPS Receiver!

October 1, 2011 by Jeremy Cook 40 Comments

GPS receivers may be available for well under $100 these days, but what’s the fun in buying one when you can build it yourself? According to [Andrew], the creator of this device, he was inspired by Matjaž Vidmar who developed a GPS receiver from scratch over 20 years ago. His article can be found here and includes some nicely hand-drawn diagrams as well as a lot of theory.

However, [Andrew’s] article is a bit more up-to-date and features plenty of theory itself. He explains how he built his four-channel GPS receiver, able to track four satellites at the same time. This is the minimum number of satellites needed to track your position using such a device.

GPS technology is quite incredible, and the amount of soldering as well as the understanding of the theory behind it required to build such a device is astonishing. Interestingly (sadly?), it seems we are beyond the time of LORAN hacks, but if you have an old one to share, be sure to send it in! For something a bit easier, maybe one could try making a GPS “cateye” to track what your pet does all day!

A Sunrise Clock For Those Cold, Dark Winter Mornings

October 1, 2011 by Mike Nathan 26 Comments

For most of the working world, the onset of autumn and winter in the Northern hemisphere means one thing – waking up well before the sun rises to get a start on the daily grind. [Brent] from Freeside Atlanta knows that routine well and decided to build himself a sunrise alarm clock in an attempt to wake himself more naturally on those dark mornings.

He bought an assortment of LEDs in varying colors including blue, red, yellow, and white, along with a few UV diodes for good measure. His goal with this array of LEDs was to simulate the natural colors of the sunrise, rather than simply slowly brightening the room. The clock uses a DS1307 RTC to keep the time, and an Arduino is tasked with lighting the LEDs about 25 minutes before it’s time for [Brent] to wake up.

He says that it seems to be working pretty well, gently waking his body before the clock radio kicks in. It certainly beats a loud buzzer!

Weekly Roundup 10/1/11

October 1, 2011 by Jack Buffington No comments

In case you missed them, here are our most popular posts from the past week.

Our most popular post was about a Chinese man who is attempting to build an octocopter that he can fly around by pairing motorcycle engines to propellers. There were a considerable number of comments on this one!

Next we have a post about a project where a 12-series PIC is used with a single inductor to create a working RFID tag.

Our third most popular post was [Bertho’s] tutorial about capacitive sensing. This is his entry into the Dangerous Prototypes 7400 Logic competition so you’ll really get to see the nuts and bolts of how this type of sensing works.

Next is a post that is about a pretty unique lathe made out of concrete. If you have the weight capacity in your workspace, this could be a nice addition to your tools.

In fifth place is a post about [Eric’s] second revision of his word clock that tells time in German!

Sustainability Hacks – External Wood Burner

October 1, 2011 by Jack Buffington 50 Comments

Sometimes sustainability is about making do with what you have. This is the wood burner that I use for my personal workshop. In my area, it is mandated by law that we have to clear brush on a yearly basis. I live on a pretty large lot so we have plenty of brush to be cleared every year. Add to that the occasional tree that falls down and all of the scraps from my shop and you have all the wood that you need to heat a shop like mine. With the exception of the work that I put into gathering firewood, my heat is free and is carbon neutral. This is somewhat of a double hack because as you have probably noticed, the wood burner is sitting outside of my workshop. My workshop is fairly large but I have it so packed full of tools that I just didn’t have room inside so I came up with this solution.

More details after the break.
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Fake PS3 Tracks Thieves All The Way Home

September 30, 2011 by Mike Nathan 73 Comments

ps3_tracking_system

One of [Wayne’s] relatives had their house robbed during a blizzard/extended power outage, and as is typically the case, none of the stolen items were recovered. His nephew’s PS3 was among the pilfered belongings, which didn’t sit well with him. Taking a cue from police “bait cars”, he thought it would be cool to fit a dummy game console with a tracking device, should anything similar happen in the future.

He bought a hollowed out PS3 shell on eBay, filling it with an Arduino, an accelerometer, a GPS sensor, a small GSM modem with a prepaid SIM card, and a reasonably sized LiPoly battery. The system usually sits in a sleeping state, but when the accelerometer senses motion, the Arduino powers up the GSM modem and sends an SMS security alert to his mobile phone. Using his phone to control the tracking system via SMS, he can request GPS coordinates and directional information, which can then be relayed to the police.

His tracking system is a great idea since hawking stolen game consoles are easy money for thieves. If there happens to be a string of robberies in your neighborhood, you could certainly rest a little bit easier knowing that your Playstation doppelganger will let you know if someone is looting your house.

Passive RFID Tag Cloning

September 30, 2011 by Mike Szczys 34 Comments

Here’s an open source RFID cloner design that is about the same size as a standard RFID key card. It doesn’t need a battery to capture key codes, just the magnetic field generated by an RFID reader. You can see the functionality demonstrated in the video after the break. By holding the bottom button as the cloner is moved in range of the RFID reader, the microcontroller goes into learning mode. Now just hold up the card you wish to clone and the LED just above the buttons will light up when it has captured the code. Now the device will act just as the original RFID tag did.

This was developed by [Ramiro], the same person who built the barebones RFID emulator we saw a few days ago. When researching that story we complete skipped over this gem. He’s posted a ton of information on the tag itself. It doesn’t look like he has any PCBs or kits left, but the schematic and code are available for download. You should check in on the design considerations section because it discusses the read/write function that isn’t built into the current version. That’s why you see some add-on components on the hardware used in the demo video.

It seems like this is a lot more user-friendly than the last RFID spoofer we looked at.

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