Zombiel3
disMember
Air to Air frequencies are just that. Plane to plane. ARTCC is the Air Route Traffic Control Centers that take over comms once the aircraft exist the airport control space and then hand them off to the destination airport
You will find ARTCC frequencies listed in the RR database for each US state. I don't know where to find the Air Control Centre frequencies in Canada.
You can listen for aircraft callsigns and track them with Flightradar 24 app on your phone.
I know the 2 closest to me are Toronto Centre and Montreal Centre because that is what I hear CFB Trenton tower handing planes off to when they fly through. I'm going to program them in.
I have Flightradar24 on my phone already.