They cover considerable ground, the supplementary features are spot-on and the multimedia "test your knowledge" page will jog ample memories.
The main story, and three more parts are coming through early November, is available here.
Two very cleverly-produced little video tributes. The first includes some FM, but it doesn't matter. How long has it been since you heard some of these?
This one focuses solely on KDKA.
Disclosure: Adrian produces the PG's audio podcasts including the weekly "Believe Your Ears" Music podcast Scott Mervis and I contribute to, and I have to say she brought the same exacting standards to this story she brings to the podcasts.