Quickly organizing the "Basic Point Defense Missile System", BPDMS, the then-current AIM-7E from the F-4 Phantom was adapted to shipboard use with surprising speed. The main developments were the new Mark 25 trainable launcher developed from the ASROC launcher, and the Mark 115 manually aimed radar illuminator that looked like two large searchlights. Operation was extremely simple; the operator would be cued to targets via voice commands from the search radar operators, and he then slewed the illuminator onto the target. The relatively wide beam of the radar only needed to be in the general direction of the target, the continuous wave signal being Doppler shifted by the moving target and showing up strongly even if it was not centered in the beam. The launcher would automatically follow the motions of the illuminator, so that when the missile was fired it would immediately see the signal being reflected off the target.