I have been having signal problems, Dish to Humax . We live in a "Fringe" area for the signal and after 15 years, the cables – Dish to receiver have started to 'perish'. Anyway, I replaced one of the cables some time ago and it was time to replace the other as the signal received on the oldest cable was 'weak'. So I removed the cable from the LNB and left it dangling whilst I threaded a new cable. However, before connecting the new cable, I saw that the same strength signal came from the Humax channel connected to the old cable (But no connection to the LNB). The cables run in cable ducting about 8 metres long.
Any ideas as to how that works ?