Flat-panels were supposed to eliminate the hulking television cabinet. But they are tethered to boxes -- cable tuners, disc players, A/V receivers -- that fill a big piece of furniture. A wireless connection lets you at least stash those peripherals out of the way. We tried out the first two cable-free HD technologies: one that uses radio waves and another that piggybacks on your home's electrical wiring. We tested them by sending video 25 feet from both a Blu-ray disc player and a Sencore VP401, a machine that produces test patterns that break up conspicuously if there are any reception problems.
Sony Bravia Wireless Link
Sony's Wireless Link uses a technology called WHDI to send data over a signal similar to Wi-Fi. WHDI favors data bits with a big effect on the picture -- say, ones that change the color of an object. It may sacrifice others, like bits that subtly affect hue.
WHDI certainly loses a lot of data. We saw that clearly with test patterns: Some finely detailed images stressed the system so severely that the screen went blank. But with a Blu-ray movie, video and audio seemed crisp and fluid. The errors in the signal were undetectable to a casual viewer.
EDITORS' RANK: 8/10
Five amazing, clean technologies that will set us free, in this month's energy-focused issue. Also: how to build a better bomb detector, the robotic toys that are raising your children, a human catapult, the world's smallest arcade, and much more.