Lose connection! help

Hello,

I have two laptops: one is a toshiba and other is acer. I also have an ipad and an iphone. The problem is whenever my modem (netcomm- NB9WMAXXn) turns off and turns back on again, it loses its wireless connection. I have to go to its settings and reset and move the modems antenna bit by bit to finally get the connection to wirelessly connect with all those devices, except the acer laptop because its fine. What should I do, please please help!