Thank you Arcy for posting this question and thanks to Abu and others who replied. I have been driven almost demented trying to get my Vu+ Uno 4K setup properly, mostly due to my own ignorance. For instance I had not appreciated my Unicable LNB only gave me 4 channels (my Vu+ has twin tuners). I had now intended to buy an 8 channel version (Opticum Red Robust Legacy Unicable 2 SCR 2, up to 8 subscribers via single cable solution - SCR frequencies: 970, 1030, 1090, 1150, 1210, 1420, 1680, 2040 MHz) but Arcy's bad experience with the lower frequencies has made me think again. Still looking.
I now have my tv working but can only set timers for 4 channels. Unicable LNB is connected to tuner A, legacy output to tuner B.
Just to add, I had to change the Tuner A Channel to User Band2, Frequency 01400 before I got a picture. Presumably the legacy lnb is using band 1.
I also found this interesting, from Abu:-
" I suppose it is because of the misconception that you need more than one tuner to record more than one service. Whereas one tuner allows multiple access to one transponder."
Does this mean that with my twin tuners and 6 'virtual' tuners, I could theoretically record dozens of channels if the transponders are favourable?
Thanks for reading this, you can plainly see I have need of further education. I find it all rather complicated, especially when the STB suddenly stops responding and has to be factory reset, starting the whole game over again.