The problem with jammers is that if you don't shield the building where you're using them, you're going to interfere with the outside which is a potential publi

The problem with jammers is that if you don't shield the building where you're using them, you're going to interfere with the outside which is a potential public safety risk (it's illegal for a reason). Of course, if you bother shielding the building, you don't even need jammers, because there's no signal going through anyway.