FEMA, along with three other major operational agencies under the Department of Homeland Security, rely on shortwave radios for two-way communications in the field. In other words, they use HF radios -- HF standing for "High Frequency," for many of their tactical communications needs. The military and many relief organizations worldwide also use HF radios extensively. You'd think that these various agencies and relief organizations could easily communicate with each other, since they are all u.