La radio or El radio

Question

Aren't both masculin and feminin acceptable? Tnx

Answer

Hola Eugene,

As it says in the lesson, “radio” is an abbreviation of “radiodifusión” and that “ión” ending is always feminine. Another similar noun is Foto which is an abbreviation of “fotografía.” In my experience a masculine article is never allowed; the abbreviation is always treated as if it were the full word.

John

Answer

Hola Eugene
In this case it's feminine as we are referring to "radiodifusión", however in some countries in Latin America, if you are talking about the radio as the gadget (radiorreceptor) you may hear it used in masculine "el radio". In Spain this would still be used in feminine. 
Saludos