Board Thread:New on Galaxy on Fire Wiki/@comment-61.173.110.147-20130224004146/@comment-6002884-20130309043729

Go to the Hangar, then at the top right corner of your screen, click on the "Ship" button. Scroll down to the Secondary Weapons section, select the EMP bombs, and hit the button to equip them.

If you can't find the EMP bombs, it's most likely that you didn't get them from the Shop. Don't worry; they're free. Just transfer them to your ship.