For sure it isn't due to signal strength, because the two devices were close, and at the same distance of about 20cm the E51 had a perfect reception. And the mobilehotspot signal was not encrypted. With a wifi scanner app on the Tab I'm able to see the mobilehotspot network, with a fairly strong signal, but when I press the widget on the app to connect, I am brought to the android wifi setup menu, where the mobilehotspot is lacking. When I manually enter the ssid, the Tab reports that the network isn't there.