How to make a radio command not work until all objectives complete?

[Pred42 10]

I have 3 objectives that need to be complete in my mission. I have 3 heli's waiting to evac but how do I set it up so that the radio command will only work after all 3 objectives are taken? If I add another trigger that says opfur not present and sync it, will that work? (sorry I'm not at home right now to try. Just wanting to know what to try later)

[f2k sel 164]

disable a channel

10 setRadioMsg "null"

to enable

10 setRadioMsg "juliet Radio"

[Pred42 10]

I guess the next stupid question will be how do you turn the channel on during the game?

[fortun 14]

Have a trigger and put the last thing he wrote in the activation field