Is my android when turned on constantly sending radio data to my provider so he can track me, or only when i am actually using the network by surfing or calling someone?
Not an Android specific question, but in short:
Unless you're enabling Airplane mode, the provider will be able to always track you. He can tell where you are at what day and time, at least with an accuracy of ~100m or better.
Why? In order to be able to receive calls (even if you don't want to make a call yourself), your device needs to connect to a cell tower. And in order to ensure you will receive that call even when moving (you might lose that signal), it needs to contact at least one more cell tower so it can easily "hand you over". That makes 2 cell towers. Based on network signal strength, it's possible to calculate rawly how far away you are from each tower at any time. With two or more towers that offers the possibility of Triangulation:
Triangulation (source: DoctorsDisruption; click image to enlarge)
As the image shows: with three towers it's pretty easy to tell where you are. Even with two that can be narrowed down to a small area.
And btw: That's how Google's "network based location" works, too – only that it additionally considers WiFi access points.