Portable receivers were rare in the thirties. Some sets come from overseas, Detrola for instance.
German, Swedish and British brands were available right before the war.

 

Portable receivers

 

Radione

Austrian Radione R2 was mostly ahead of the time, other brands look more or less like suitcases or handbags.

Expensive investment

Portable receiver was an expensive investment. Every portable receiver from the thirties that still exist in Finland can be regarded as rarity.