Check the grammar rules online. The answer is it depends how it an acronym is pronounced: if you start an acronym with a vowel sound then you should use "an", otherwise you should use "a".
"An FM" or "A FM"? Which is better?


If you say "fried" chicken, you don't say "ef".
Yes, but we're talking about the acronym for it. "FC" starts with "ef"

A one, and a two and a three . . . (one sounds like won). A one hundred dollar bill. As pointed out above, it's the sound that counts. The trickiest word - history related. It was an historical speech (technically correct). It was a historic speech (usual spoken and written).

A one, and a two and a three . . . (one sounds like won). A one hundred dollar bill. As pointed out above, it's the sound that counts. The trickiest word - history related. It was an historical speech (technically correct). It was a historic speech (usual spoken and written).
You voiced my thoughts.
I say "an" because when you say 'f' aloud, you say "ef". So that starts with a vowel sound.
But FM stands for Fide master, which starts with a consonant sound, so is it good grammar to say "a FM"?