[Arran]

I will have to look up the diagram but in most Philcos they didn't bother using a dedicated tuned circuit for each pushbutton, they just used a pair of trimmers for each preset, one connected to the antenna coil, and the other connected to the oscillator coil. It's easy enough to check the broadcast band antenna coil, just use an ohm meter on the primary and the secondary, if it has continuity on both winding then the trouble is elsewhere. I would have a look though the front end of the radio and see if there are any burned looking coils related to the AM broadcast band, maybe the antenna was hit by lightening?
Regards
Arran