Panoramic radio receiving system US 2279151 A Chuck N7RHU: Panadapters Quote: "...The panoramic spectrum display, invented by Marcel Wallace in the 1930s, provides a radio operator with a graphic display of radio signal amplitudes at frequencies close to the signal to which his radio is currently tuned..."
Panoramic radio receiving system US 2279151 A Chuck N7RHU: Panadaptors Citat: "...The panoramic spectrum display, invented by Marcel Wallace in the 1930's, provides a radio operator with a graphic display of radio signal amplitudes at frequencies close to the signal to which his radio is currently tuned..."