[ARC5] ARC's first range receiver of 1929

[zakariya.abu at yandex.com]

Colleagues,

I've just found a reference on the Smithsonian Institution's website 
that the ARC Model D of 1929 was the first commercial navigation 
receiver. See here:

https://airandspace.si.edu/multimedia-gallery/14185hjpg

Does anyone know the specs of this set? Did it cover the 200 to 400 kHz 
range only?

73,

Jan SP5XZG