Wireless routers have a usable range of approximate 60 feet in all directions. However, several factors can limit the effective range of your router. For example, old cathode ray tube televisions, baby monitors and even old microwaves can cause interference with the Wi-Fi signal a router sends out. Also, routers are hindered by physical obstacles such as thick brick walls and sub floors. This hinders the signal's ability to penetrate walls and floors to provide adequate signal to wireless users in other rooms. Converting a second wireless router into a range extender makes your wireless network twice the size thus enhancing your coverage.
Create a secure connection between the router and a computer to give yourself access to the router's GUI (graphic user interface) so you can turn off the DHCP (dynamic host configuration protocol) server. To do so, connect the router's LAN (local area network) port to a Cat5 Ethernet cord. To complete the connection, plug the other end of the cord into the Ethernet port located on the back of your computer or the side of your laptop.
Access the Internet via the web browser of your choice and enter the default router address into the address field. If you do not know the router IP address you can obtain it by going to the "Start" menu and then select "Run." Place, "ipconfig" in the command box and press "Enter" or "Return" on your keyboard. A black screen appears. Locate, "Default Gateway" from the list. The number to the right is the IP address of the router. Enter that number, with the dots, into the address bar of your browser.
For Linksys and Belkin routers, enter "admin" into the username field and leave the password field blank. For D-Link routers, enter "admin" into the username and password fields.
Access the "Basic Setup" section of the GUI and locate the section for DHCP. For example, on a Linksys router, the section is titled, "Local DHCP server." Disable the server by selecting the radio button next to "Disable" and then save the settings. The router is now a range extender.