Used a Futaba xtal. It's a single conversion, or some people call it the short version. Anywho, it should be listed in the catalogs as single conversion. I think some people have had some success with other xtals, but the Futaba seems to be the most popular. I also believe that I picked up somewhere that the 4-1 in the Blade was broadbanded enough to handle either low or high band. Everything I know just about this little beast I picked up off one of the forums here. You just have to spend some time researching. Did that sound like a disclaimer???? Ha! Ha! I'm pretty sure with what I've told you here, but hopefully someone else will jump in if I'm not. There's people on these forums that has forgotten more than I'll ever know about the Blade.