You're just converting the Belkin router into an AP (access point). To do that, you need to give the Belkin a static IP in the same network as the primary router (Actiontec). For example, if the primary router is using 192.168.1.1, perhaps make the Belkin 192.168.1.2, just as long as the IP you choose is not used elsewhere, such as the DHCP pool of the primary router. Now disable the DHCP server on the Belkin and connect it to the primary router LAN to LAN.