on 20-11-2013 08:28 PM
on 20-11-2013 09:06 PM
I suspect the interference your digisender is picking up is caused by the wireless connection to your Sky box - you could check by temporarily disabling the wireless service in your Sky box settings. (I could never get a sender to work properly for this reason). A 5.8GHz sender may work better, as it's less prone to the 2.4GHz interference caused by most wireless routers, but has less range.
There are alternative ways of connecting to your Sky box - an IO Link (www.sky.com/accessories) would enable you to install a simple coax connection between your box and the other TV. Or a long HDMI, SCART or composite cable. Or HDMI over ethernet (cat 5 or cat 6 cables). I use an HD wireless sender which is completely inteference free, but didn't come cheap.
It's not possible to split the dish cables I'm afraid.