crystal quarts and frequency generators

Hi all,
Please excuse my ignorance, while I stumble trying to understand the whole aspects of Rife Technology.

I follow the spiritual path via Science (quantum physics) and a splash of faith. Being that my passion is technology, (computers/internet and Science in general), I'm strongly considering getting into rife technology "healing". I've research a bit here and there, and quite shocked to realise that people have associated "guides" with the technology in the form of "the doctrine". WOW! I wish I knew this technology years back!

Can someone help me bridge the gap between rife's use of quartz crystals and the newer modern day frequency generators? To me, it makes sense to have a quartz crystal, but it seems that the newer frequency generators don't use it. How come? to me, it seems it shouldn't work...