The radios are turned on to use the Air Raid which is located down the staircase outside of the PAP room outside of the big door.

As far as I know, there are 3 radios to activate before getting the Air Raid.

1. Go to the armory which is after the $850 debris by spawn courtyard, and on a table to the left of the entrance is the radio. (Screenshot[i.imgur.com])

2. Go to the Sniper's Nest which is after the $1000 debris by spawn courtyard, and on some boxes and sandbags to the right side of the perk machine is the radio. (Screenshot[i.imgur.com])

3. Go down the staircase outside of the PAP room and follow the hallway down and go through the right door. After that, follow the stone path on the ground and take a right turn. To the right of the Torii (those Japanese gate thingies) theres 3 barrels, the middle barrel has the last radio on it. (Screenshot[i.imgur.com])

If I'm missing any radio locations, please tell me and I will fix it as soon as I can, thank you