I now ask whether I can connect TC o my Imac by USB to use the TC just as an ordinary external hard disc for back up via Time Machine.
No, the Time Capsule must connect to the network using an Ethernet connection (preferable) or via wireless.
The USB port on the Time Capsule is only used to connect another hard drive for additional storage.....and/or a printer.
I maaged to get the Time Capsule connected using the Powerline for ethernet to TC. There were 4 queries highlighted by a red 4 in Airport Utility but options to ignore where there and selected.
Green light on TC and backup started, not for long as my earlier this year problem re Sparse Bundle Error 1 has delayed the backup. Referring back to Mr Pondini instructions I got as far as restarting my Mac after which the connection was broken although green light still showed on TC. My back up disc no longer shows in disc utility.
Trying to reconnect has been unsiccessful so far.
Wd appreciate help.