GSP-830 User Manual 156 3. Check the marker ID box. 5 markers, 0 to 4, are available. 4. Enter the frequency to each marker in MHz. 5. Select normal (N) or delta marker. Example: Marker 0 & Delta 1: the delta marker shows the difference between marker0 and marker1. 6. The display is updated with markers in red color. The marker values are listed at the bottom of the display. Exit program Operation step Click the exit icon or press Alt key + F4.