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5.11 - Signal Processing

5.11.1 - Auto Noise Floor

ANF determines the average level of the noise floor over time and adjusts the position of the RF display wave downwards to position the baseline two divisions from the base of the plot.

Note: ANF has no effect upon signal demodulation — all effects are upon the visual data displays. Additionally, ANF has no effect upon the waterfall display.

Note: When ANF, SdB is disabled ( SdB) (because the plot no longer retains a constant relationship to amplitude.)

5.11.2 - Smooth Noise Floor

SNF uses advanced DSP techniques to adjust the display of the spectrum and waterfall noise floor to make it easier to see signals, and to reduce disruption by impulse signals such as lightning static.

Tip: →Right-click SNF allows you to set the smoothing and threshold parameters of the SNF function. These two settings interact; play with them a bit to see how that works. Generally speaking, you should set the RF spectrum and waterfall up to look the way you want them to before you adjust the SNF parameters.

The result is less complexity in the waterfall at low signal levels, and more distinct visualizations of stronger receivable signals in both the RF spectrum display and the waterfall display.

Note: SNF has no effect upon signal demodulation — all effects are upon the visual data displays.

SNF can be used instead of display averaging (in the Display dialog — set Averaging to 1 to disable) or at the same time as settings above one. Adjust to taste.

5.11.3 - Low Pass Filter

You turn on the low pass filter with LPF. You adjust the low pass filter frequency with Lpf.

Low pass filtering is useful when there is a lot of hiss, or you think you're hearing too much pre-emphasis.

When recalling memories, if you want the memory recall action to set the low pass filter state and frequency, make sure MFL is on.