[Arran]

 What Mondial said makes sense, the model 118 is an updated version of a model 18, some model 18s had the standard AM broadcast band alone, and others had AM broadcast and the old fashioned police band which was basically an extension of the prior above 1500 KC, much like a model 60 would have. So Philco being Philco, when they wanted to come up with a new model, rather then engineering and tooling up for a new chassis they took the model 18 and modified it's front end to allow for a proper shortwave band, probably by their logic hard core shortwave listeners could go out and buy a model 16 , those that were casual shortwave listeners but would more then likely listen to dance bands or soap operas could buy the 118.
Regards
Arran