I've recently started trying this mode with WSJT-X and I'm really enjoying it. One thing bugs me in that I feel like I'm missing a basic understanding though - the two different frequencies used. For example: On 80m I tune my radio to 3.573 MHz (the "FT8" frequency for 80m, right?). But then within WSJT-X I transmit and receive on 1150 Hz (just picked that numner as an example). Does that mean the actual frequency I'm using is 3.573 MHz plus 1150 Hz, or 3.574150 MHz? How do those two numbers interrelate?