Pink bands!

[Straz]

I have a very hazy memory that during the 1960s, a team of four boys represented CH in a television quiz.
I don't believe it was Top of the Form, but possibly a junior version of University Challenge. This was in the days of black and white TV.
My abiding memory is that it was revealed - possibly in The Blue or maybe in a TV listings magazine - that the four boys all wore bands that had been dyed pink! This was because on black and white TV, pink came across on screen as a brighter white than regular white.
Can anyone confirm my hazy memory? And, if so, what was the TV programme, was it on BBC or ITV, and how did CH do in the competition?