I wouldn't see any problem in putting the receiver part through the x ray machine but if unsure check with the manufacturers. I see no problem in not putting it through the x ray and just telling them when you come to it that you don't want it to go through, they usually are ok with it as long as you get it swabbed for explosives. I can't imagine that the PDM receiver is any different to a telephone or laptop with Bluetooth though, x rays don't effect them. It's different with the pump receiver as that's attached to you although easy to detach I don't want to go to the faff.
Going anywhere nice?