Radio Club - All 23 Channels - What does this mean? It is like a Zona Thing ?

A few years ago I saw someone wearing a hoodie top with this on it. I still to this day cannot work out what 'radio club' and 'all 23 channels' actually means but I did work out it's a clothing line from a US place called Carhartt which had some collaboration going with an Australian placed in Melbourne called Perks and Mini. But what's the actual meaning? Seems to be 'unexplained' like the Zona Thing.