The ones we used to hear on the shortwave in Europe were enciphered transmissions to agents from their controllers. Most of the numbers broadcasts originated in the East Bloc, but there's no reason to suppose that the West didn't use them for agent communications as well.
At least in the Russians' case, the cipher keys were one-time pads issued to the agents in personal meetings or through dead drops - a key element of vulnerability in their networks. Marc de Piolenc Tyler Durden wrote: > > Oh yeah, another thing I wanted to ask about, before I forget. > > It's somewhat well-known that throughout the South pacific, there are "radio > stations" that do nothing but broadcast the real-time reading of number > sequences, but no one seems to know just why.
