Your Station panel

DX Station panel

Prediction Direction panel

• From the DX Station - when selected, your ability to copy the DX station's signals is predicted

• To the DX Station - when selected, the DX station's ability to copy your signals is predicted
  
  

Prediction Path panel

• Short - when selected, propagation is predicted via the short path between your station and the DX station

• Long - when selected, propagation is predicted via the long path between your station and the DX station
  

Propagation Web Sites panel

You can populate each box in this panel with a URL that provides timely propagation information; clicking a box's Go button directs the specified web browser to display the box's URL.

Solar and Geomagnetic Parameters panel

The buttons on this panel provide access to historical, current, and forecast parameters that influence HF propagation:

Beacon panel

Clicking the Monitor button displays PropView's Beacon Monitor window, which can be used to assess actual propagation by monitoring beacons in the NCDXF/IARU Network.

Generating a Propagation Forecast

To determine where and when you can hear a DX station at a particular location,

1. select the desired Forecasting Engine and technique

2. set the Prediction Direction to From the DX Station

3. specify settings on the Main window's Parameters tabs:

• In the Conditions panel,

  • specify the UTC Date for which the forecast is to be generated (note: double-clicking the Date box will populate it with the current UTC date)

  • update the smoothed sunspot number by clicking the U button to the right of the SSN box (note: the smoothed sunspot number changes monthly)

  • update the geomagnetic K-index by clicking the U button to its right (note: SpotCollector, if running, will automatically update this setting from WWV reports)

  • set the Avail box to the desired probability of successful communications (50% produces aggressive forecasts; 90% produces conservative forecasts)

  • specify the required signal-to-noise ratio in the SNR box, or use the Condition panel's Mode selector to set the required signal-to-noise ratio as a function of the mode to be used

• In the Your Station panel,

  • specify your station's Latitude and Longitude or Grid Square (note: these settings will be automatically specified if DXView is running)

  • specify the level of Man-made RF noise at your location

• In the DX Station panel,

  • specify the DX station's Latitude and Longitude or Grid Square (note: if DXView is running and Track DXView Loc is enabled, DXView's selected location will be used

  • set the DX station's expected power output

4. Set the Prediction Path panel to Short for a prediction of short path propagation, or to Long for a prediction of long path propagation
   
   
5. Click the Predict button

To instead determine when and where a DX station at a particular location can hear your station, set the Prediction Direction to To the DX Station, specify your station's TakeOff angle and Power in the Your Station panel, and specify the DX station's Man-made RF noise level in the DX Station panel. If the Frequency-dependent Settings panel's Enable box is checked and  Commander is running, PropView will set TakeOff and Power from the Frequency-dependent Settings as a function of your transceiver's current band.

When you click the Predict button, PropView will create the scripts required to drive the selected forecasting engine, and then direct that engine to generate the prediction. When the forecasting engine has completed its computation, PropView will render the generated numeric forecast graphically on its Main windows Prediction tab. If the selected forecasting engine is IONCAP (a DOS program), execution can take several minutes on slower machines running some versions of Windows. The identity of the engine used to generate a forecast is displayed in upper-left corner of the Main windows Prediction tab, along with the forecast date.

The forecast graphically displayed on the Main window's Prediction tab shows time on its horizontal access, and frequency on its vertical access. A frequency scale labeled in MHz is provided along the left margin, and a wavelength scale labeled in meters is provided along the right axis. If a prediction To the DX Station was generated for a specific band, a magenta ball appears to the right of the primary transceiver's current band, if that band is present in the forecast. Otherwise, if Commander is running, a magenta ball appears to the right of the primary transceiver's current band, if that band is present in the forecast. 

A line of text immediately above the graphical prediction specifies

• SP for a short path prediction, or LP for a long path

• the Required SNR used to generate the prediction

• "from" if From the DX Station was selected; "to" if To the DX Station was selected

• the location of the DX station and its callsign if available

• the length of the path between your station and the DX station (in miles or kilometers)

• the band whose frequency-dependent settings were used, if To the DX Station was selected and if Frequency-dependent Settings were enabled

Below the graphical prediction's time axis, PropView displays two horizontal bars indicating the solar position at your station and at the DX station; in these bars, yellow means "sun is up", black means "sun is down", and grey means "twilight"; to display a Solar Colors  panel that provides a color key for each of these conditions, check the Prediction tab's Show Color Keys box.

The brown Vertical Time Index line shows the current UTC time, but can be dragged to any time of day; check the Show Current Time box to make the Vertical Time Index resume tracking the current time, and to automatically update the Date.

If the Plot Critical Frequencies box is checked, PropView displays the following frequencies hour-by-hour

• the lowest useable frequency (LUF) in black (not present if VOACAP's SNR & Prob technique was used to generate the forecast)

• the 90%-confidence Maximum Useable Frequency (MUF) in blue

• the 50%-confidence MUF, in green

• the 10%-confidence MUF, in red (not present if VOACAP's SNR & Prob technique was used to generate the forecast)

If the Show Open Bands box is checked, PropView displays horizontal lines for each amateur band for which propagation is possible and for which the box for that band in the Prediction Bands panel on the Configuration window's Prediction tab is checked. The width of each line indicates the likelihood that propagation will occur.

For forecasts generated by any forecasting engine's LUF & MUF technique,

• if the band is higher in frequency than the LUF, and lower in frequency than the 90%-confidence MUF, then its associated line is 3 pixels in width

• if the band is higher in frequency than the LUF, and higher in frequency than the 90%-confidence MUF, but  lower in frequency than the 50%-confidence MUF, then its associated line is 2 pixels in width

• if the band is higher in frequency than the LUF, and higher in frequency than the 50%-confidence MUF, but  lower in frequency than the 10%-confidence MUF, then its associated line is 1 pixels in width

For forecasts generated by VOACAP's SNR & Prob technique,

• if the Required SNR is forecast to be achieved on 80% or more of the days of the month, the associated line is 4 pixels in width

• if the Required SNR is forecast to be achieved on more than 60% but less than 80% of the days of the month, its associated line is 3 pixels in width

• if the Required SNR is forecast to be achieved on more than 40% but less than 60% of the days of the month, its associated line is 2 pixels in width

• if the Required SNR is forecast to be achieved on more than 20% but less than 60% of the days of the month, its associated line is 1 pixels in width

Allowing the mouse cursor to hover over an opening forecast by VOACAP's SNR & Prob technique will display three parameters for the selected time and band:

1. the predicted Signal-to-Noise Ratio, in decibels

2. the percentage of days of the month that the Required SNR will be achieved

3. the predicted number of hops among ionospheric layers

You can generate new short path or long path predictions by clicking the Prediction tab's Predict SP or Predict LP buttons respectively.

Interpreting PropView Graphs generated by any Forecasting Engine's LUF & MUF technique

After generating a prediction for propagation between two locations, check the Plot Critical Frequencies box and uncheck the Show Open Bands box.

The black curve represents the lowest useable frequency (LUF) as a function of time. Any frequency lower than the black curve will not support communications due to absorption.

The blue, green, and red curves provide a statistical range for the maximum useable frequency (MUF) as a function of time. The actual MUF will be at or above the blue curve with 90% confidence, at or above the green curve with 50% confidence, and at or above the red curve with 10% confidence. Any frequency above the actual MUF will not support communications, due to insufficient reflection. To display a Critical Frequency Colors  panel that provides a color key for each critical frequency color, check Prediction tab's Show Color Keys box.

So at any specified time, you can identify which frequencies will likely support communication between the specified locations: they are bounded on the low-end by the black curve, and on the high-end by the statistical range between the blue and red curves. You can use the green curve as a kind of "expected MUF" curve; if you're an optimist, use the red curve for this purpose.

To make it easier to see what ham bands are open when, uncheck the Plot Critical Frequencies box and check the Show Open Bands box. Horizontal lines represent enabled ham bands lying between the LUF and statistical MUF. The thickest lines indicates openings based on the 90% confidence MUF (the blue curve), and the thinnest lines indicate openings based on the 10% confidence MUF (the red curve).

If you now check the Plot Critical Frequencies box, the relationship between horizontal lines and critical frequency curves should be apparent.

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