Until now, most of us had only 2 sources of an EMP to worry about. The first, and arguably the least severe is solar related. Geomagnetic activity from solar flares and CMEs have been known to knock out power gids, albeit for a short time. High altitude nuclear detonations seem a little more worrisome for preppers, as the high intensity EMP from such a blast is believed to cause very widespread and detrimental effects on power grids and electronics.
Preppers have been researching ways to protect their electronics, generate their own power, and protect and repair damaged vehicles. There are countless disagreements about grounding Faraday cages or not, discussions on older vehicles without modern computers and what parts to stock up on to repair them, and numerous forum and blog posts about what types of alternative power generation could be used after such an event.
Just when we thought we were making headway on the topic, along comes a new threat regarding damaging EMPs. Enter Boeing's CHAMP weapon. CHAMP - Counter-electronics High powered Advanced Missile Project is the latest EMP device in the world today. A recent test flight of CHAMP successfully disabled power, computers, and even the video cameras set up to record the event. It is now evident that the scientific and military world have a really good understanding of EMP power and it's uses and effects.
This, of course, raises a whole new set of concerns from the prepper community. Just because the US is the first to disclose the existence of such a weapon, doesn't ensure that other, less western friendly countries don't already have the technology, or won't possess it soon. Although I can't see terrorist organizations using this exact model, I can see how they could adapt the technology into other delivery systems. Of course, there is also the concern that our own governments could us this weapon against it's own population, but as you all know by now, I really don't subscribe to such paranoid conspiracy theories.
Take a look at this video from Boeing...