The radio is a part of the core TTT components. Sure it doesn't get used a lot but I've seen it used now and again. Place a C4, then wait 30 seconds and start playing death noises on the radio. People will flock to it like geese.
I love the radio, use it to troll alot, I usually place it in key points to make people go where I want them to, then I do what I feel like doing to their innocent lifes....heheheheh.