New Zealand is still waiting but hopefully wont be long before we all are given a chance to add this feature to the SDS range of radio’s…..

Well here is the operation manual for you to swat up on so its all go when it becomes available in AU/NZ

Waterfall Feature Operation Manual
The Waterfall Feature is available for the SDS100 and SDS200 scanners. It covers a
user-selectable span or band of the radio spectrum to show you graphically the radio
transmissions that are present. The Waterfall feature quickly shows you how active a
span or band of the spectrum is. When you see a transmission displayed, you can
navigate to it to listen to it.
Since all transmissions occurring in the selected span will display at the same time,
you’ll be able to see possible relationships between transmissions. For example, you
might see simultaneous repeater transmissions on multiple frequencies or find a
repeater input frequency associated with the repeater output frequency. The strength of
signals will provide clues about the nature of the transmissions or how far or near the
transmitters are. Alternatively, they will tell you the relative strengths of transmitters.
These observations will enable you to gain a quick understanding of unfamiliar radio
systems or of a new location.
Go to and
 Register your scanner (if you haven’t done so already).
 Download the latest version of Sentinel.
Use Sentinel to download the most current firmware for your scanner model.
Purchase a License Key for the Waterfall Feature from or from your
scanner store.
On the scanner press Menu->Settings->Upgrade and select Upgrade Waterfall.
Enter the entire License Key, including the dashes. This is done by rotating the
PUSH/FUNC knob to select characters and the arrow soft keys to advance the cursor.
When done, press E (Enter). If entered successfully, the Waterfall Feature will be
available for use.
Starting Waterfall
To start the Waterfall function, press Menu and use the knob to scroll backwards to
select Waterfall and press E. You will see a display headed by “Waterfall” that shows
several options for starting it as well as for adjusting various settings.
The starting options are as follows:
Start Waterfall Current Settings – a default band and settings that you can
Start Preset Waterfall One of several named bands and settings that are pre-
defined for you by Uniden.
Start Custom Waterfall One of several named bands and settings that you can
Understanding the Display
The scanner’s display is divided into two panes. The upper pane is called the FFT
Display and the lower pane is called the Waterfall Display.
FFT Display
The FFT Display shows a real-time graph of the strength of radio signals and
background RF noise. Grid lines on the horizontal axis depict frequencies, and grid
lines on the vertical axis depict signal strength levels.
The signals or noise being received across the selected span are plotted in white.
The Marker
In the center of the graph, a vertical line (defaulting to green) is displayed. This line
represents the frequency that the scanner is currently tuned to and is called the Marker.
The current frequency can be changed either by entering a frequency from the
keyboard and pressing the Enter key or by turning the knob.
When using the knob, the frequency changes by the current value of the Step with each
knob click. This works well for small frequency changes but is probably too slow to
move to a more distant active frequency. If you press Function before turning the knob,
the frequency will change by a much larger amount, allowing you to quickly move to the
area of the more distant frequency. When you get closer to the desired frequency,
press Function again to revert to movement by Steps to fine tune to the exact desired
When the user changes the current frequency, depending on the setting of parameter
Set Marker->Marker Position, the Marker will either move (Position Adjustable) or
will remain centered in the display (Fixed in Center Screen). Position Adjustable is
the default.
In the Position Adjustable mode, the marker moves (and the receive frequency
changes) but the lower and upper limits of the span remain fixed.
In the Fixed in Center Screen mode, when you change the receive frequency, the
marker stays put in the center but span shifts accordingly, so the lower and upper span
limits change.
Other Information Displayed
The area above the FFT graph displays the following information:
Line 1:
 Data about a transmission being received, for example “P25”
 Current date (month and day)
 Current time (hours and minutes).
Line 2:
 The name of Band being received. This is either one of the pre-programmed
bands that can be selected or a user-defined band name.
Line 3:
 Current frequency being received in large numbers
 Step size
 Modulation Type
Waterfall Display
The Waterfall Display is a continuous display of transmissions and noise levels. It
shows you a rolling 10-second window of activity. The most current, most recent
observation is at the top and the oldest observation is at the bottom. Because the
Waterfall Display color-codes the strength of signals or noise received and because
observations move downward in time, the display resembles a waterfall, and hence this
feature’s name.
Transmissions appear as lines whose lengths reflect the length of the transmissions.
Signal strengths are shown by the color of the lines. Each color represents a particular
range of signal strength and there are 5 signal ranges and 5 colors. The feature’s
default colors are adequate for most purposes, but the user can customize them.
Other Information Displayed
Line 1:
The Span size
The current setting for Gain
Line 2:
 The Current Frequency that the scanner is tuned to
 The current volume setting
 The current squelch setting
Soft Keys
To Scan Span Hold
Scanner exits
the Waterfall
feature and
Changes the value of the
frequency Span of the band being
At span size settings above 2.88
MHz, the scanner cannot receive a
transmission unless the Hold soft
key is pressed first.
Freezes the
display, allowing
user to tune to a
frequency before
disappears from the
display. User can
unfreeze display by
pressing this key
again (Sweep).
Step Max Hold MF->CF
Change the
value of
frequency step
size or select
Auto. Each
time this key is
pressed, the
value of the
step changes.
Signals displayed in the FFT
Display remain displayed after
transmission stops so you can
observe all peaks over a period of
time. Pressing the function key
and this key again returns display
to real-time mode.
Moves the Marker
(and frequency
being received) to
the Center
Frequency of the
Adjusting Display Screen Space Allocation
While the waterfall feature is running, you can conveniently change the amount of
screen space dedicated to each type of display (FFT and Waterfall) by pressing
Function followed by the nine (“9”) key on the keypad, which is labeled “9 DISP”. To
return to the waterfall, simply press “E” after making your selection.
Available choices are:
FFT: 25% / WF: 75%
FFT: 50% / WF: 50%
FFT: 75% / WF: 25%
FFT: 100%
Assignment to Search Key
For convenience, you can optionally assign the waterfall function to one of the three
search keys on digits 1-3 on the keypad. These are labeled SRCH1, SRCH2, and
SRCH3. This is done by pressing:
Menu->Search for->Set Search Key->Search Key n->Waterfall
Where “n” is a number 1 through 3.
Once this is done, when the scanner is held on a channel, you can start the waterfall
feature, using the Current Settings, by pressing Function and the SRCHn key that you
assigned to waterfall.
RF Gain
The scanner’s RF Gain defaults to the recommended value of Automatic. This setting is
preferred and adequate in most cases. The user can adjust the RF gain by selecting
one of 16 available gain levels, numbered 0 through 15, or can choose Auto.
In an area with nothing but weak signals, the user may increase the RF gain in order to
receive more signals. In an area with very strong signals, the user may decrease the
RF gain to compensate. Be aware that changing the gain simultaneously affects the
strength of the background noise as well as signals.
NOTE: If you increase the gain too much in a strong signal or noisy environment, the
display will saturate and distort, making it impossible to obtain correct information.
To change the RF Gain setting, press the Function key and press the zero (“0”) key on
the keypad, which is marked 0 LVL. The setting is changed by turning the knob.
Start Waterfall Restarts the last waterfall
session used.
Start Preset Waterfall
Select and start a waterfall
session for a pre-defined
Air Band
CB Radio
FM Broadcast
Ham Radio (various band
Racing (two choices)
NOAA Weather
Start Custom Waterfall
Select and start a waterfall
session for one of ten
user-defined (and named)
Program WF Custom Band
Define a custom band. Up
to 10 custom bands can be
Edit Name
Set Center Frequency
Set Modulation
Set Step
Set Span
Edit Current Edit certain parameters of
the current FFT Display.
Set Center Frequency
Set Modulation
Set Step
Set Span
Set Signal (FFT) Display
Change the amount of
screen space dedicated to
each type of display (FFT
and Waterfall).
FFT: 25% / WF: 75%
FFT: 50% / WF: 50% (the
FFT: 75% / WF: 25%
FFT: 100%
Set Signal (FFT) Type
Choose the method used
to represent signals in the
FFT Display.
Line: Shows signal
strength levels as one
continuous plot line (the
Bar: Shows signal strength
levels as solidly filled bars.
Set Max Hold Turn Max Hold on or off On
Off (the default)
Set Max Hold Time
Set the amount of time that
display is held when the
user presses Hold.
3 sec
10 sec
Infinite (the default)
Set Marker Adjust Marker position and
Marker Position: Position
Adjustable or Fixed in
Center Screen
Set Marker Width:
Narrow, Default, or Wide
Set Color
Customize the colors used
to depict signal strength
ranges in the Waterfall
Customize the Marker
See a demo of your
selected color settings.
Reset Waterfall Display to
factory settings.
There are 5 signal strength
ranges available,
numbered 1 through 5 in
increasing order of
© 2023 Uniden America Corporation,
301 International Pkwy Suite 460, Flower Mound, TX 75022
Rev. 1.0 Dec.21 2023 First release