trap jammer

[BURN]

Player A has a face up monster and a set Trap Jammer
Player B has a set Stealth Bird and a set Astral Barrier
Player A declares an attack with his face up monster
Player B flips Astral Barrier

Can player A use Trap Jammer to stop Astral Barrier?

 

[daivahataka]

Yes you can activate it, by chaining it to the activation of a trap, at any time during your battle phase. If the Astral Barrier was already active though, then you couldn't use Trap Jammer against it since Trap Jammer must be chained to the initial activation of the trap.