As the electrons fly from the cathode, they are attracted to the positive mesh screen. ”If you just had a solid metal piece there, the electrons would impact and create X-rays,” says Giesselmann. But because of the mesh, ”most fly right through.”
Those electrons then find themselves on the other side of the screen. They are then pulled back toward the mesh, most again falling through it, only to be attracted to it once again. ”So now they are oscillating wildly through the screen, back and forth—that’s the microwave oscillation,” says Giesselmann.
The trials this week at the USAMDC at Redstone Arsenal are just the first round of tests. Electric-field probes and other equipment will be set up to measure the effect of the detonation. ”We are still proving to [the U.S. military] that it can be done in such a small package,” Giesselmann says. ”There’s a big difference between doing it in a lab and getting them to believe [that] you can do it in the field.” After that, Giesselmann anticipates further testing.
”They’ll need to do testing to make sure it can withstand acceleration,” says Schamiloglu. ”They’ll want to see if you can put this in a platform and it will take all the forces and still operate.”
The same vircator that makes the microwaves can also be driven by a nonexplosive power generator—one that doesn’t self-destruct. However, these generators tend to be larger than FCGs. Texas Tech is working on using a kind of compact power source called a Marx generator in the hopes of making a portable directed energy weapon—a microwave cannon. Giesselmann says the first application will likely be car zappers, a method of stopping vehicles by using HPM to destroy the electronics and shut the engine down. ”This is a lab prototype that cannot be considered deployable in any stretch of the imagination,” says the Army’s Altgilbers. ”It requires a big truck to even bring the unassembled parts to the test area.” Altgilbers says the device ”is not a consideration” for disabling IEDs, stopping cars, or disrupting communication, ”now or in any future version.”
