The thread on HDMI streaming menntioned streaming TV boxes, so I got interssted and did some research.
And came up with TVheadend - a TV server that can read a DVB card or dongle and allow streaming of TV programs to suitable clients.
So I installed in on my Liniux Mint Server and yes, it works pretty well.
Howver, be warned, this installation for me was everything that gives Linux a bad name. The code would not install without some manual installation having to be done.
And the instructions were totally opaque. Definitely written by a progranmmer for other programmers.
BUT it works . I can watch TV on any computer on the network that has VLC installed, and indeed after installation of the appropiate 'app', on my friggin smart phone.
And recording is a doddle too.
So its a great DIY replacement for a TV stremaing box+PVR but not for the faint heraterd. You can however download a complete OS installation that takes out some of the pain and will allow an obsolete PC to become a video server.