Yeah, it's actually both. The S3A has the 14 extra bandswitch positions for the crystal deck and is otherwise the same as the original S3. The S3C has the same extra positions and is otherwise the same as the later model S3B. Even if you had the 140 crystals, you'd have to change them ten times in the deck to get "full general coverage" of HF. You could add a synthesizer to a lot of receivers to make them general coverage!