The USB-N66 is a pyramid shaped device that glows purple, and plugs into your computer's USB port, where it can be an 802.11n USB adapter. It can also work as a wireless hotspot, and there's a high power mode that requires two USB ports to provide the extra power.
The device works as advertised, and provides throughput (using ixChariot) of 140Mbps. There's an installation CD that makes the device far more confusing to set up than it needs to be. To use it as a USB adapter you only need to plug it in and provide the required security information.
The EA-N66 looks just like the USB-N66 in that it's a small pyramid that glows purple. It's an 802.11n Ethernet bridge that supports three spatial streams. You can use it to support one Ethernet device, such as a television set.
The instructions that come with the EA-N66 tell you that setup is simply a matter of pressing the WPS button on the device and on the router. Trouble is, there's no WPS button on the device. You need to set it up with a computer with a wired Ethernet interface, and then browse to the Web based configuration page. Once there, all that's required is a couple of clicks. Once in place, it works as expected, and it supports 140Mbps throughput, just like the other 802.11n devices.
If there was a common theme with these devices, it's that, with the exception of Netgear, the instructions are lousy. By that I mean they are frequently simply wrong. Worse, the software that comes along may not be useful, and in the case of the D-Link adapter resulted in slower operation than the tests showed without it. Again, that was not the case with the Netgear device. Each of these devices actually turned out to be useful in some way, but not always in the way the manufacturer seems to have intended.
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