[Arran]

Packard employed Philco built radios from the early 1930s right up until the middle 50's, then switched to Delco, apparently because some Packard execution was smitten with the Wonderbar radios G.M made. The silly part was that Philco car radios used electric pushbutton tuning, with tuned circuits, whereas the Wonderbars used electromechanical tuning, with a spring loaded solenoid affair, almost a throwback to motor driven tuning of the 1930s. Both work but the electromechanical tuning is more hit and miss, maybe because the Wonderbar radios physically moved the dial along meant it was doing something more in this executive's mind then the Philco radios, Chrysler obviously knew better since they used mostly Philco and Motorola radios.
Regards
Arran