Stepper Directed HDTV Antenna


Broadcast TV has come a long way from adjusting the rabbit ears on top of the set just to get a fuzzy black and white picture. While nowadays there are often HD signals broadcast in most areas, it can often still be critical to redirect an antenna to get the best possible signal. By harvesting a stepper motor from an old 5 1/2″ floppy drive, and using a PC’s parallel port to control it, this adjustment can be handled automatically. Broadcast tower locations are easily found online, and once you have calibrated your stepper to face North, you are on your way to free HDTV reception.

What we would like to see is this antenna attached to a HTPC, and some kind of script to automatically direct the antenna for the best possible signal for the current channel. If anyone out there makes this happen, be sure to let us know.

A ride into space, but nothing fancy

[Luke Geissbuhler] wanted to send something into space, a fun project his kids could get in on too. Instead of sending up a suite of electronic components they went with consumer electronics. The key element, an HD camera to record the event, is protected by a styrofoam shell and soft foam padding. To help ensure that the device was recovered an iPhone also made the trip, running a GPS tracking program that continuously updated the package’s location. To combat the ill-effects of severe cold some chemical hand warming packs also joined the flight.

As you can see after the break, it was a success. The camera documented an incredible ride, with a balloon rupture at 19 miles above the earth (that must be a calculated height as there’s no altimeter in the package). The pod came down gently thanks to a parachute and was recovered just 30 miles from where it launched.

[Read more...]

Hacking the Western Digital TV media player


Western Digital recently released a media player that attaches to your TV and allows you to play HD media straight from an external USB drive to the television. With a price point of about $100, it’s strange that the device hasn’t made more of a stir in the consumer electronics market. Of course, if it exists, someone will hack it, though. Clever hardware and software hackers have already managed to get an alternative firmware running on the device, allowing for packages like a web server, RSS reader, Apple trailer viewer, and other linux-based packages. It’s good to see a device with so many software mods so early into production.

Related: OpenPogo, an alternative to Pogoplug software

Massive Etch A Sketch from TV screen

[Jeri] put together an absolutely massive Etch A Sketch for The FatMan and Circuit Girl show. She had removed the DLP chip from an HD rear projection TV and decided to repurpose the 52inch screen. The movement mechanism uses pulleys from screen doors with nylon lines. The two sets of lines are fed in a criss cross pattern so that the parallel lines move in the same direction. The lines move tent poles in the x and y which controls the movements of the golf tee stylus. It’s driven by two high torque motors from $9 Harbor Freight 18V drills. They tried several different powders, but ended up using aluminum powder from an original Etch A Sketch because it sticks to everything. It will eventually be hooked up for IRC bot control once they get a large enough h-bridge.

[via adafruit]

UHF power harvesting


[Alanson Sample] and [Joshua R. Smith] have been experimenting with wireless power transfer for their sensing platform. Their microcontroller of choice is the MSP430, which we used on our e-paper clock. They chose it specifically for its ability to work with low voltages and they discus its specific behavior at different voltages. The first portion of their paper uses a UHF RFID reader to transmit to the sensor’s four stage charge pump. They added a supercap to provide enough power for 24 hours of logging while the node isn’t near a reader. For the second half of the paper, they use a UHF antenna designed for digital TV with the same circuit and pointed it at a television tower ~4.1km away. It had an open circuit voltage of 5.0V and 0.7V across an 8KOhm load, which works out to be 60uW of power. They connected this to the AAA battery terminals of the thermometer/hygrometer pictured above. It worked without issue. The thermometer’s draw on a lab power supply was 25uA at 1.5V.

It’s an interesting approach to powering devices. Do you have an application that needs something like this? For more on wireless power, checkout this earlier post on scratch building RFID tags.

[via DVICE]

DS + 50D timelapse examples

We covered [Steve Chapman]‘s Nintendo DS control for his Canon DSLR in September. He’s since improved the software so that it has a timer for sunset/sunrise amongst other things. He also shot about 30GB worth of timelapse images while in Vancouver and assembled a couple test videos. He’s still working out the processing to take full advantage of the 15megapixel images. We look forward to future results since YouTube is now using a much larger player for high def content.

YouTube testing even higher quality videos

YouTube, purveyor of some of worst looking flash video is finally getting their act together. We posted the other day about embedding videos using &fmt=18 to get higher quality YouTube videos. It seems the awesome knob has now been turned up to &fmt=22. All of the previous tricks should work, just use 22 instead of 18. This all depends on the highdef version being available. Now they just need to get rid of the grainy preview images.