http://forums.station.sony.com/dcuo...go-go-gadget-guide-to-everything-gadgets.318/ For all your gadget needs.
I came to give some tips, but checked that guide before I wrote anything. As a former gadgets controller (will return to it, eventually) I´ll say, that guide is all you need.
I'd worry about it when you hit 30 when you can buy the gear for that specific role. I suggest getting the Archangel/bloodbat PVP armor to start you off, it'll up your vitality for the Tier1 alerts.
Take a look at the Gadget guide that has been already been suggested. Below is the link again: http://forums.station.sony.com/dcuo...go-go-gadget-guide-to-everything-gadgets.318/ At a minimum you need Sticky Bomb to provide ranged Power Over Time and Defibrillator to provide Burst Power. Sticky Bomb is also useful to stun and juggle opponents. Defibrillator boosts your Might & Precision. Controllers are expected to provide Power Over Time at ALL times in Group content. When POT is active there will be a Green Lighting Bolt under your name. If you are the only Controller in a group, you should keep POT active at all times. If there is another Controller in the group, work with the other Controller to determine who will provide POT. A player will lose POT if they get knocked out. If a cut scene activates, POT stops. So a Controller should cast POT power whenever the Green Lightning Bolt disappears, whenever someone revives from being knocked out and after any cut scene. You should provide Burst Power to Healers when they are low on Power if you expect them to Restore your Health. You should provide Burst Power to Tanks when they are low on Power if you expect them to keep opponents off you. It is helpful to have a Defense Debuff in your loadout for Boss fights. A Supercharge that provides Group Power can also be helpful. I recommend having a multi target Crowd Control power in your loadout to incapacitate multiple opponents.
Iconic Tree - take Word of Power, best supercharge a troll can have IMO Otherwise all the other posts are on the money
I will need to agree word of power is the greatest troll SC and that guide covers everything you will need to know about gadget trolling