This is the part that confuses me. My first radio was 2.4 ghz so I've got no experience with those 72 mhz radios with replaceable crystals. If swapping crystals is so dangerous, why don't other countries have laws against it? And why are the crystals sold? Are planes constantly being shot down outside the US? Or is it mostly the legal issue that stops people from doing it in the US? I saw the post earlier where someone said a plane was shot down due to a bad crystal swap. Is that common? It just seems odd that something that sounds so dangerous is only forbidden in one country.