I have been running a Time Capsule+X-modem setup. The wireless connection was good throughout the house. I had suffered the usual problem of the hard disk in the Time Capsule failing on 2 occasions, and had reverted to a large external hard disk connected to the TC via USB. Time machine worked just fine with this setup.

Recently I have had to go from this TC+modem setup, to a BT Hub (for reasons of broadband reliability in a rural area).

My problem is that if I plug the external hard disk into the BT Hub, the Time Machine backups no longer work.

As a temporary solution I have reverted to having 2 networks running, the BT Hub for the internet, and the TC for the backups. Switching networks allows me to have either internet or backup, but not both at the same time.

I heard that there was a way of connecting the two devices while maintaining the internet connection through the BT Hub. Can anyone provide very clear instructions on how this might be done? I will be most grateful.