To make it clear why people are saying it’s ambiguous:
(A minor memorial for) (Leo Laporte on terrestrial AM radio)
vs
(A minor memorial for Leo Laporte) (on terrestrial AM radio)
The latter is not only just as grammatically valid as the first, it is also a sensible article headline, the idea that someone used AM radio to broadcast a memorial for Leo Laporte.
Can you not see why people would read it as the latter?
(A minor memorial for) (Leo Laporte on terrestrial AM radio)
vs
(A minor memorial for Leo Laporte) (on terrestrial AM radio)
The latter is not only just as grammatically valid as the first, it is also a sensible article headline, the idea that someone used AM radio to broadcast a memorial for Leo Laporte.
Can you not see why people would read it as the latter?