Η πιο γρήγορη περιγραφή που έχω δει για να συνδέεις 2 router στο ίδιο δίκτυο:

Connecting two SOHO broadband routers together.

Configure the IP address of the secondary router to be in the same subnet as the primary router, but out of the range of the DHCP server in the primary router. For instance DHCP server addresses 192.168.0.2 through 192.168.0.100, I'd assign the secondary router 192.168.0.254 as it's IP address.
Disable the DHCP server in the secondary router.

Setup the wireless section just the way you would if it was the primary router.

Connect from the primary router's LAN port to one of the LAN ports on the secondary router. If there is no uplink port and neither of the routers have auto-sensing ports, use a cross-over cable. Leave the WAN port unconnected!

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