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How come the Frequency Display doesn’t let me select the exact Frequency I need?

April 26, 2017display doesn’t exact Frequency let select

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How come the Frequency Display doesn’t let me select the exact Frequency I need?

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You probably have turned off Fractional-N mode (see also “Resolution” FAQ under Performance section). With fractional-N mode disabled, the frequency granularity that can be generated is 1/65536 of the granularity when the fractional-N mode is enabled. A warning message in the LCD display shows “FractOff” to indicate that the fractional-N mode is turned off. When the fractional-N mode is turned off, the frequency will still be increased or decreased in 10µHz steps when pressing the UP/DOWN buttons, but the display will show the actual frequency that can be generated by the DDS (closest match to the desired frequency) once the button is released. The advantage of turning off the fractional-N mode is that the system generates an exact mathematically deterministic frequency without residual, fractional errors that are present in fractional-N mode.