I think you need to be British to really know about Blue Peter. It was an improving TV show for children with interviews with interesting people conducted in a sensible manner. You can still get a bit of a chuckle out of a British audience with the phrase "Here's one I prepared earlier." It means the presenter, instead of actually building the model car out of toilet rolls or peach pits, suddenly produces a beautifully crafted, finished example.
John Noakes is referred to by middle aged men as if he were still on the show -- and they were still young enough to watch it. His sheepdog was almost as famous as he was for a time. He was last seen by me in 1987 promoting a government-sponsored prize for schools (in my memory the prize was given for the best slogans about keeping dogs on leads, but that may just be the brain damage).