On 07/22/2010 04:43 PM, Russ Allbery wrote:
David Smith<sidicas2@gmail.com> writes:Just about all computers here in the USA with the exception of (some) battery chargers use B-Plugs.. You can plug A-Plugs into B Sockets.. It's a safe bet that all the dorm rooms will have at least one B-Plug, but it would be good to get a confirmation and whether or not there are any guarantees in regards to that...The additional prong on a B plug is ground, which is mostly unnecessary with US wiring for most devices. It's common for US laptop power supplies to have an A plug. You can't be absolutely guaranteed to have a B plug available, so if you have the choice and you're talking about a laptop and not something like a hair drier, I would go with an A plug. That being said, any building whose electrical wiring has been built or rennovated in about the last forty years probably has B sockets.
More laptops have B plugs these days, FWIW. Incidentally I would be shocked if any visitor to the USA encounters an A socket. Yes some old A sockets exist, but are exceptionally rare due to the number of devices that require a B socket. I'd be certain that all the outlets in the Columbia dorms are B sockets; after all, Columbia students are probably bringing PCs or monitors, both of which usually require a B socket.
One other thing I should mention: USA GSM frequencies aren't necessarily the same as the frequencies you might use elsewhere. Not all GSM phones will necessarily work in the USA.
If you want a phone with a US number, you can buy a Tracfone prepaid one for $10. Not sure, but I'd imagine there are NYC retailers that sell these on the spot. (Note that international calling *from* a Tracfone can be somewhat limited.)
-- John