This is something that's always intrigued me and I've never quite been able to figure out how and why this happened. 

As everyone here almost certainly knows, AM radio in this part of the world is spaced out by 10 kHz from 530-1710 on the dial. That's why it was always 1050 CHUM instead of say, 1059 CHUM, which - no matter how you say it - still sounds weird to me. But before digital radio became a thing across the sea, most North American DXers would never be able to figure out who was where if they listened in what my grandparents used to euphemistically call "The Old Country."

Stations were at 696 or 1583 or some weird configuration like that. The famous Radio Caroline pirate station off the coast of Britain was on 648 and 1368 when it first came on the air. BBC Radio 5 is one of the few still using AM. You can find them on 693 and 909. I can't even imagine trying to tune those in.

Then there's ABC Radio Canberra in Australia, which is at 666 on the dial. The devil you say!

Also, their FM is often different from ours. You'd might not hear a 104.5 CHUM FM overseas. Instead, it could be at 104.4 or 104.6. Many of their FMs seem to be even numbered (with some exceptions) while ours are all odd. 

Does anyone know why they opted for the spacing they did and why the world didn't all get together and do the same thing? I prefer numbers that end in zero. It's just a lot cleaner and less confusing. But Europeans obviously got used to it. What made them choose their system while we chose ours?