An L of a place for radio communication! (4)

I believe the answer is:

lima

I'm a little stuck... Click here to teach me more about this clue!

But I can't explain it at all! Could you help me understand?

(Other definitions for lima that I've seen before include "Mail it to Peruvian city" , "Kind of bean" , "Mail to capital of Peru" , "Edible bean; capital city" , "Mail to Peru'd capital" .)

Want a hint initially instead of a full solution? Install my app