Steve watched, amused, as dark and light heads bent over the backpack sized mass of machinery spread out on the table. It was currently taking up a little more surface area than a backpack, since the two men had partially disassembled it. Steve leaned towards the young man standing next to him. "Dr. Venkman...are you absolutely sure that thing isn't going to blow up?" he asked quietly.
"Oh, totally sure," Venkman said, waving one hand negligently. "Egon knows what he's doing. We've been knocked around plenty while wearing the proton packs."
"You know," Tony said suddenly, "if you added two more magnets over here, replaced these heat sinks with another ion emitter, and added a gram of fissionable material, you could use a second stream to balance the fluctuations in the first."
"Yes, but if the frequency variation shifted even fractionally during use the resulting explosion would level New York City," Egon said contemplatively.
"The arrangement is going to add stability," Tony insisted. "It won't shift. Here, let me show you--" he reached for a second, intact proton pack.
In unison, Steve and Venkman took a long step away from the lab table.