Had a quick look through my footage of the 1975 German GP, there seems to have been a total of nine mounted TV cameras that year.

CAM1: Within the Südkehre of the start/finish loop, capturing the cars coming down the straight, then panning full circle to follow them around the loop and down the back straight.

CAM2: On the entry to Hatzenbach, covering the first three corners of that section. Located inside of the Ring between the first and second turn.

CAM3: Situated somewhere atop of Ex-Mühle, covering Wehrseifen, Breidscheid and the climb towards the Bergwerk right hander.

CAM4: On the hill next to the Steilstrecke, covering Klostertal, the climb towards Karussell as well as the first half of that turn.

CAM5: Panning along the Karussell from the inside of the turn for close-up shots of the cars going through and then exiting the corner up the hill.

CAM6: Exit of the Karussell section with the fast left-hand sweeper towards Hohe Acht.

CAM7: The quick right turn on the exit of said sweeper and the entry into Hohe Acht.

CAM8: Looking towards the exit of Tiergarten in the background, Hohenrain in the foreground, then following the cars through that double chicane onto the start/finish straight.

CAM9: Mounted atop the grandstand right at the finish line, enabling it to cover the entire start/finish straight (plus the pits and the score board).

And then back to CAM1 again, and so on. The huge gaps between CAM2 and CAM3 (Hatzenbach >> Wehrseifen), CAM3 and CAM4 (Bergwerk >> Mutkurve), and CAM7 and CAM8 (Hohe Acht >> Tiergarten) seem to have been covered exclusively via helicopter, at least that year. I've seen b/w footage from the 1960s with at least two additional cameras, one looking down towards Flugplatz, the other situated at Brünnchen, though these may have been on film, not for TV.