Quote Originally Posted by KerryC View Post
The antenna works, as it passes through the TiVo to the TV. So it looks like the internal tuner has blown
The signal will pass through merely with power connected. There is no software involvement here.

As for the tuner being faulty ("blown") I doubt that very much. Never had a faulty one yet in hundreds fitted and although there is a slim chance it could be the tuner I can say that in 100% of cases people casting doubt on the tuner it has always been a software fault.