Prototype Nokia phone recharges without wires | Hacker News Reader

Prototype Nokia phone recharges without wires

tech.yahoo.com

45 pointstomh13 comments

Wow, the title here really down plays what it actually does. Wireless power has been around for a while, my electric toothbrush uses that. But scavenging power from existing RF in the environment, that's just cool :)

I wonder if you can stick this phone in the microwave and charge it with a quick 30s?

I have a question to someone with a physics/electronic background:

If you implement this idea in a large number of devices, wouldnt a concentration of these devices block/suck the RF signal, impeding any transmision?

I don't think you can suck an electromagnetic wave without bending space-time like a black hole does. These devices will simply be radio opaque.

If you place a perfectly black object on the floor of a room that has a glowing bulb on the ceiling, the room will get relatively teeny bit darker as the carpet won't be reflecting as much light as it was reflecting before but this black object can't suck in light that is not coming its way. So, no matter how many such black objects you place on the floor, the room won't become dark.

Unless you are talking about a Great Wall of China of these Nokia phones that is tall enough to cross ionosphere...

Without wires, and without a dock. It's drawing power from ambient radio waves; this is brilliant. This isn't another one of those wireless charging attempts where you need a dock to blast it with EM radiation.

This kind of ambient RF pickup was described in a 1970s Scientific American "Amateur Scientist" column. It required an antenna the size of a frying pan, however, for approximately the same net wattage. I am curious what Nokia's trick was (assuming the achievement was carried out in real life, rather than only on paper.)

My English friend claims he was able to hard-boil an egg in three days with his GSM phone. I've tried in the States and I think he's full of it. But this gives me pause - there is a level of ambient energy from RF devices that is considerable.

It is a little bit disconcerting to think that there's enough power just floating around to... "do something real".

Kind of like a crystal radio, but on a much larger scale.

(A crystal radio apparently harvests something on the order of tens of microwatts while in operation)

I love this kind of thing. It's effectively a "perpetual motion" machine, but because it uses waste energy generated from somewhere else, it avoids that pesky "laws of physics" thing.

I really think we'll see more of this in the future, perhaps even on much bigger scales.

Can't the Pre already do this?

No, the Pre has a landing pad which you put it on. (i.e. it's "specifically designed with a transmitter and receiver in mind"). This phone will not require a landing pad, and will recharge ANYWHERE you happen to be (as long as radio waves penetrate the area).

The touchstone is awesome though. While I still can't get over the fact that I paid 1400% markup for it, that thing does bring a smile to my face every time I use it.

Reply on news.ycombinator.com