[Ron Ramirez]

As far as I know, all 37/38-610 sets, as well as Canadian 37/38-3610 sets, are five tube radios with no RF amplifier stage. And, yes, all 37/38-610 sets have three bands.

Interesting that the set you saw had an extra socket hole in the RF deck, Arran. But not surprising, given Philco's penchant to use up as many parts as they could, in any way they could...