WinWarbler PSK Reception

WinWarbler Online Help Contents

WinWarbler simultaneously demodulates and displays PSK31, PSK63, or PSK125  transmissions on three separate frequencies. It provides three receive channels, each with its own display pane; channel numbers are displayed to the left of each display pane. The receive modulation setting controls PSK31 and PSK63 demodulation for all three receive channels. Choose PSK31, PSK63, or PSK125 operation by clicking the appropriate button on the Main window's Mode panel.

WinWarbler's PSK Broadband Decode function monitors signals in the PSK band whose audio tones lie in the range from 100 Hz. to 3500 Hz., decoding up to 47 such signals simultaneously and extracting callsigns to display a Stations Heard list. To enable this function, check the PSK Receive panel's BBD box; to display the Stations Heard window, double-click this box's BBD label, or click the Display Stations Heard button on the Config window's Broadband Decoding tab.


The tuning display at the bottom of WinWarbler's main window provides a visual indication of PSK activity across a 4 kHz frequency range; the bottom of this range is set by the contents of the xcvr freq selector (in kHz), located in the QSO information panel. Note that your transceiver's bandwidth and filter settings may attenuate signals in parts of this range. You can select a waterfall or spectrum display, using settings in the Tuning Display sub-panel; the FFT averaging setting controls the computations driving either display. A waterfall display can be presented in monochrome, or synthetic color using a color lookup table devised by AE4JY; waterfall gain and baseline clipping settings allow you to further control this form of tuning display. The spectrum display's trace color is set by the trace color setting, and its background color is fixed at black. You can set the spectrum display's gain independently from that of the waterfall display.

If sub-band highlighting is enabled, the frequency scale above the tuning display is rendered in green for frequencies within PSK sub-bands, and in red for frequencies outside of PSK sub-bands; you can customize the definition of these sub-bands.

 The tuning display shows the current frequency of each receive channel:

You can change the colors of these traces via WinWarbler's display settings. You can control the width of these traces via the frequency trace width setting. Instead of traces, you can choose to be shown each channel's current frequency with colored triangular markers hovering above the tuning display.

If two receive channels are set to the same frequency, only one trace will be visible in the tuning display. If the transmit panel's net control is not checked, WinWarbler's transmit frequency will appear in the tuning display as a red trace.

To change a receive channel's frequency, first select that channel by clicking anywhere in its display pane - the channel label to the left of the display pane will turn red, and the receive panel will indicate the selected channel. Click in the tuning display to set the selected channel frequency, which will appear in the receive panel; frequencies in the lower 100 Hz or upper 500 Hz of this range cannot be selected. If there's a nearby signal, as defined by the search range setting, WinWarbler will set the selected channel frequency to this signal's center frequency. The AFC (Automatic Frequency Control) limit setting controls WinWarbler's ability to track a signal whose frequency is changing; you can enable or disable AFC via the AFC checkbox. A Doppler-tracking AFC algorithm can be selected by clicking the Doppler AFC button; when this Doppler-tracking AFC is selected, the AFC checkbox's label is rendered in red. You can switch Doppler-tracking on and off by clicking on the AFC checkbox's label.

You can both select a receive channel and set it's frequency simultaneously with a single gesture:

The two buttons in the Receive panel's lower left corner allow you change the current channel's receive frequency to the next lower frequency or next higher frequency signal respectively. These functions are not selective as to modulation -- they locate the next signal of any kind, including transient signals. With the mouse cursor in the transmit pane or in the QSO Info panel, depressing the Alt key while striking the Down Arrow or Up Arrow keys activates  the next lower frequency signal or next higher frequency signal functions respectively.

The Tuning Display panel provides controls that let you increase the vertical height of the tuning display, and zoom on the horizontal (frequency) axis. You can only increase the tuning display's vertical height if doing so would not make WinWarbler's window height larger than your monitor can display. Changes you make in the tuning displays' vertical height while in PSK mode do not affect its vertical height while in RTTY mode, and vice versa. When the tuning display horizontal zoom is greater than one, the horizontal pan control lets you select the magnified frequency segment to be viewed.

The signal quality indicator in the receive panel displays the quality of the signal being received by the selected channel; this is a measure of the signal's phase noise, not its amplitude. Each receive channel maintains its own squelch threshold setting, which is established by clicking within the signal quality indicator while that channel is selected; responsiveness of the squelch for all three channels is controlled by a single squelch speed setting. When the current channel's signal quality is below it's squelch threshold, the indicator is red; when signal quality is above the squelch threshold, the indicator is yellow, green, or blue as a function of the current channel.

When the signal quality is above the squelch threshold, the signal strength indicator in the receive panel's lower-right corner provides a measure of relative signal strength, ranging from 0 to 99.

The IMD (intermodulation distortion) panel displays both the instantaneous IMD and the maximum observed (peak) IMD; the peak IMD can be referenced by the <peakIMD> macro substitution command. The peak IMD is cleared 

The circular vector display in the receive panel displays the phase changes of the signal being received by the selected channel, in degrees; a 0-degree phase change is represented by a vector pointing "north", a 90-degree phase change by a vector pointing "east", a 180-degree phase change by a vector pointing "south", and a 270-degree phase change by a vector pointing "west". Properly-tuned BPSK signals should show only 0-degree and 180-degree phase changes; properly-tuned QPSK signals should show only 0-degree, 90-degree, 180-degree, and 270-degree phase changes. The vector display's trace color is set by the trace color setting; its background color is fixed at black.



Information decoded from a receive channel's frequency is sequentially appended to its receive pane. Each receive pane has a vertical scrollbar along its right side, allowing you to view information which has scrolled off the pane. The only limit to each receive pane's information retention is the amount of free space on the disk drive hosting WinWarbler. You can change the font name, style, size, and color used to display this information via WinWarbler's display settings

The three receive panes are separated by two "splitter" bars. You can move a splitter bar by placing the mouse cursor overtop it; when the mouse cursor changes to a double-headed arrow, use the left mouse button to drag the splitter to its desired location, reallocating available screen space between the adjacent receive panes. If the splitter bars are set so that a channel has no visible receive pane, then no trace or marker for that channel will be shown on the tuning display.

To freely scroll a receive pane, you must first suspend the pane's display of incoming information; do so by clicking on the color-coded panel to the left of the pane you wish to scroll. A pane's channel number blinks while it is suspended. To resume the display of incoming information -- including that which arrived while the display was suspended, click on the color-coded panel to the left of the pane. You can suspend a pane for up to an hour without loss of incoming information.

To copy text from a receive pane to the Windows clipboard, use the standard Windows left-click and drag gesture. This gesture automatically suspends the pane. Click on the color-coded panel to the left of the pane to resume the pane's display of incoming information.

To facilitate logging, double-clicking on a word in a receive pane copies that word to the appropriate QSO Info panel item. 

The contents of the QSO Info panel items are maintained separately for each receive channel; whenever you switch channels, these items are updated to reflect whatever information you have captured from that channel. This makes it easy to incrementally capture information as you monitor several QSOs.

Clicking the right mouse button over a receive pane produces a pop-up menu with five commands:

Checking the Receive panel's BBD box enables Broadband Decoding. In this mode, WinWarbler deploys  47 monitor channels across the audio band from 100 hertz to 3500 hertz, each configured to search for PSK31, PSK63, or PSK125 signals within its 72 hertz range. Callsigns are automatically extracted from QSOs detected by these monitor channels.

To replay the last 25 seconds of received audio, click the receive panel's W25 button. This feature is primarily used after repositioning a receive channel frequency, allowing you to decode a previously-missed transmission.

Under abnormal conditions, loss of incoming data can occur; this condition is signified by the appearance of a red vertical status bar in the receive panel; resting the mouse cursor over the status bar will cause an explanatory "tooltip" message to appear. The red vertical status bar will be automatically hidden after 10 seconds.


Transceiver Control

WinWarbler automatically interoperates with Commander, an transceiver control program for Alinco, Elecraft, Flexradio, Icom, Kachina, Kenwood, TenTec, and Yaesu radios. If WinWarbler and Commander are running simultaneously, the TX selector in WinWarbler's Xcvr Freq panel will automatically track your transceiver's frequency as you QSY; it does not matter in what order the two programs are started. 


Optimizing the Audio Offset Frequency

The frequency shown in the Receive panel is the sum of two components: your transceiver frequency, and an audio offset frequency in the range of 50 to 3500 Hz. Your transceiver's filters may make it difficult to receive and/or transmit signals that fall near the lower or upper ends of its audio passband. If Commander is running, clicking the Opt button directs it to change your transceiver's frequency so that the audio offset frequency of current receive channel moves to the value specified in the optimal offset sub-panel of the Receiver panel on the Configuration window's PSK tab. Since the transceiver frequency and audio offset frequency are simultaneously adjusted, you can use this function during reception and lose no more than a character or two. The audio offset frequencies of the other two receive channels and the monitor channels (if broadband decoding is enabled) are appropriately adjusted to compensate for the change in transceiver frequency. You can also activate this function by depressing the Ctrl key while right-clicking in the  waterfall or spectrum display; if the waterfall right-click box is checked, you can activate this function by right-clicking in the waterfall or spectrum display without depressing the Ctrl  key.

Depressing the Ctrl key while clicking the Opt button will also disable AFC for the current receive channel.

The Opt button is disabled if Commander is not running; it is also disabled during transmission.