Time Capsule switches on, but not visible in AirPort Utility

I have just moved house.

New ADSL modem/router, no problem setting up network. Trying to 'extend' network with Time Capsule (and wireless backing up) as I had in the previous house without a problem. When I use AirPort Utility to scan for wireless devices (eg AirPorts), with the TC switched on, it doesnt appear in AirPort Utility.

The light is flashing amber, but it alweays did that.