I remember Radio Caroline and Radio Luxemberg, broadcast from a ship out on the Channel so they weren't under the rules there were then. I too hid 'under my covers' to listen to them.
There was always some sort of 'whooshing' sound on Lux, which you had to put up with!
Who remembers Jack Jackson, and his cat then? He ran a show with records only published by Decca, (spin sound of 'decca decca decca'), and his cat would 'miaow, miaow' because apparently it was always sitting on his lap when he broadcast! He was just as good much later on on his new programme, where he would pop in short clips from funny shows, and make us all laugh - he was incredibly funny and so good at his job, with none of the screeching and yelling from the kidults we get these days!
I'll never forget the Sam Cooke song, 'Chain Gang' which he'd play every Sunday evening!