On Tue, 08 Jan, 2008 at 12:39:09 +0100, Carlos E. R. wrote: > The Tuesday 2008-01-08 at 06:47 +0100, Jon Clausen wrote: > >> On Mon, 07 Jan, 2008 at 16:40:48 +0100, Carlos E. R. wrote: >> >>> It would be possible to design one. The device only needs to monitor the >>> presence of power in the usb power line coming from the laptop, and 1mA >>> would be enough to trigger the base of a transistor that would in turn >>> power up the device. It could even be designed around an >>> optocoupler/triac >>> to power up the AC side of the device. >>> >>> You just pay an engineer, and he'll do appropriate wonders :-) >> >> Too late, it's been done; >> >> http://www.elsparefonden.org/public-and-commerce/products/energy-saving-equipment/Elspareskinne > > Better: > > <http://www.elsparefonden.org/public-and-commerce/products/energy-saving-equipment/Elspareskinne/facts-and-figures/how-the-elspareskinne-works> > > But that doesn't say how this particular piece works. Typically it would > use a relays to switch off the rest of the equipment, but a relays draws > significant power from the usb bus of a portable running on battery. What I > described were methods to do the same as already known to exist, but > designed for laptops.
riiiight... I didn't realize what you meant. Elsparefonden is not a vendor of anything, it's a trust that does research on, and gives advice about reducing powerconsumption in general. Hence the above doesn't pertain to any *particular* device. I guess that most of those thingies basically just use the power from the USB to hold open (or closed) a relay, which turns on the mains. And that power would come from the battery of a laptop. http://www.elsparefonden.org/public-and-commerce/products/energy-saving-equipment/Elspareskinne/facts-and-figures/if-computer-cannot-turn-off-elspareskinne suggests that the whole concept may become obsolete, if Wake-On-USB ends up being the norm... But I agree that a version designed for laptops would be good. /jon -- YMMV -- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
