The Key of F# — Dobro

F# major harmonises to F# – G#m – A#m – B – C# – D#m – F°; F# minor to F#m – G#° – A – Bm – C#m – D – E. A caller does not say any of that. They say the key and then hold up fingers, and the whole circle is expected to translate.

F# is not one of the four keys a bluegrass circle usually calls, so when it comes up it is because a singer needed it — and somebody in the band is capoing to make their shapes fit.

Learn 1–4–5 in F# until your hand goes there without asking, then 1–6m–4–5 and the 2–5 that walks into a tag, and most of the repertoire is already playable in this key.