It was called The Secret Life of Bob Monkhouse. I think there might be a very poor quality version of it on YouTube.

There was documentary done a few years back on the comedian Bob Monkhouse and about his obsession archiving media, a lot of which were thought to be lost forever. He had multiple VHS players set up around his house to record things in an era where not many of the general public had one. He also kept tv guides and had written into the margins if there was a change in the schedule. He was actually taken to court in the 70’s for copyright infringement but the case was thrown out, though quite a few items from his archive were seized and never returned.