Understood Sailor Steve.
I see it this way; sometimes in game design, for the sake of enjoyable gameplay, certain concessions have to be made.
Yes, a particular island might be transmitting all the time, but the player will not know which island. Or, at the mission startup, perhaps two or three possible locations could be given, ie: "Leave Pearl, search here and here to intercept IJN transmission".
So you would not know where exactly to go to intercept the transmission. It has to be searched for. You may get it, you may not.
If it was too hard to find, then it would become pointless and not fun. So you have to make a concession of making it 'available' to a degree.
Lots of variable can be done. It could be a normal mission that tells you go and patrol zone X, but while there you may/may not intercept a transmission with intel, depending on how well you scan your radio. In the meantime, there would also always be other targets around to go for as well. But the real motherload of carriers would be in the transmission, if intercepted.
Just playing around with ideas. Suggestions definately welcome.
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