You can perform special functions relating to wav files recorded during strip charted observations. When combined with the ability to perform unattended wav recordings, these simple functions allow you to correlate wav file segments with chart events and save those wav file segments that are of special interest.
For example, let's say you wanted to record a Jupiter noise storm in the middle of the night but could not be present to manually operate the wav recorder controls. You could use the Radio-SkyPipe Wav Recorder scheduled recording capability to record a wav file that covered the likely duration of the storm, say two hours. This would be a rather large wav file, perhaps hundreds of megabytes in length (depending on your sound format). Keeping files of this size would quickly use up most hard drives and most of the file would not contain Jupiter burst sounds anyway. Wouldn't it be great just to save the portions of the file which did contain bursts?
You could use threshold triggering, but this method can lead to many files
generated by random interfering signals and is susceptible to failure when the
background signal level varies. Jupiter decametric strip chart signatures do
have certain characteristics, a certain "grassiness" and a limited
duration, but the strip chart alone cannot definitively identify the
signal. Experienced Jupiter observers can often however, say with some
confidence that a signal is Jupiter by listening to it. These observers
can also usually discern that many interfering signals are not
Jupiter. So the ear, in this case, is useful for sorting the data, and it would
be best to record the entire observation period and later filter by listening..
Beginning with RS-P version 2.3.0, wav files that have been saved in the same directory as a data (spd) file are automatically associated with the data file when the data file is loaded. Previous versions of RS-P allowed only a single wav file to be associated with a data file. Multiple wav files may now be associated with a single data file.You may also manually associate a wav file with a data file as described below.
Associating the Wav File with the Chart
Assuming we have set our strip chart and wav files to record during the observation period, we can at some later time refine our observation. First the strip chart would be loaded into the main Radio-SkyPipe window, (this will not work in a review window). Then under the Wave menu item under the title bar of the main window, select Associated Wav Files. The window below appears:
The associated wav files are listed. You may Add additional wav files that were not detected automatically (perhaps because it was saved in a different directory or not named using the standard nomenclature). Files may also be removed from the list or deleted from the drive. Show Info will produce a window with embedded metadata and information about the wav file format.
Above we show the strip chart shows the two files listed as gray background behind the trace. Closer examination would show that the background is really composed of a large number of vertical lines called wav markers. You may toggle the wav marker visibility under View / Tools / Show Wav Markers. The color can be configured in the color configuration window.
Selecting and Keeping Selected Parts of the Wav File
You could scan through your chart visually looking for anything that might be a Jupiter or other desired signal. When a possible signal is noted, you might then use the zoom button to isolate the part of the chart that seemed significant. Now, you would right click the chart and select Play Wav for this View from the drop down menu. If the wav file completely overlaps this part of the chart, the chart view will appear unchanged except for the appearance of a red vertical bar that tracks the portion of the wav file being played. If the wav file only overlaps a portion of the present view, the view will be trimmed to match the portion of the wave file that does correspond. The wav file will play for the corresponding view and you can decide if this is indeed a real Jupiter signal or something else. (A note could be made in the observer log to that effect.) If you want to stop the wav file while it playing press the Esc key.
Let us say that this would be a portion of the wav file that you would like to save. Again right click on the chart and this time select Rec Wav for this View. The portion of the associated wav file that corresponds to the chart view will then be saved as separate file. If the new wav file has the same beginning point as another wav file in the same directory it will have a number ( _000 to _999) appended to it's file name to prevent overwriting.
After you have saved all the pieces of the wav file that you wanted, you can then delete the original large file by again right clicking on the chart and this time selecting Delete Wav File.
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