Help: Simultaneous spots

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For more precise comparison of two nearby transmitting stations, you can analyse reports where both stations were heard by the same receiver at the same time. These reports will be in near identical conditions, so the SNR values for the two reports should give a good indication of how strong the two signals are compared to each other.

This allows comparison of stations without needing as much averaging as would be needed if comparing reports from different times (to compensate for varying conditions) or from different receivers (to compensate for different effectiveness of receiving antennas and equipment).

This is useful for comparing antennas.

DXplorer provides a graph summarising the differences in SNR for matching pairs of reports, plus some statistics about them. The report pairs are shown in a table below the graph, and can be exported as a CSV file so that you can conduct your own analysis of them.

Synchronising WSPRlites

To maximise the number of simultaneous spots from two WSPRlites:

This will cause the timeslots that are pseudo-randomly selected for transmission to be the same for both WSPRlites.

Duplicate reports

Some receivers report the same transmission multiple times with different frequencies and SNR values. These reports are excluded from the analysis by default because it is difficult to tell which SNR report is the accurate one.

To include these reports in the table and analysis, enable the "Include receivers who report duplicate spots" option. All possible pairs of reports will be included, and duplicates will be highlighted in pink in the spots table.

Only the specific reports where the same transmitter is reported more than once by the same receiver in the same timeslot are excluded, not all reports from those receivers.


This comparison feature is only available to Premium users.

Some distance and azimuth values will be slightly different from those displayed by WSPRnet. This is because WSPRnet uses a slightly incorrect method of calculating the latitude and longitude for 4 character locators, which gives a location that is not the centre of the grid square, but is instead slightly off centre. DXplorer recalculates the distance and azimuth values using the correct coordinates.