Rift Quest:Infernal Devices  

In the circles are Fae Camps. And at the edges are the Infernal Amplifiers. The Amplifiers are on about a 1.5 Minute or Less respawn timer. Much shorter than the mobs. So moving to the northern circle to get the rest is not necessary. It is entirely possible to work your way around the camp, kill the guarding Fae and loop around again.

Rogue Tip: Because the camps are not as condensed as many other lower level camps are, you can Lost Hope the guard, get the Amplifier, move to the next one, Lost Hope him (or whatever sap move you have) and steal it. This is only to avoid combat though. I was on Envoys From The East quest so I didn't do this.

An Infernal Device