Thanks to GTplanet at (here). 

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This was the conclusion from the posts. Several nice answers were used to draw this conclusion. 

…I’ve been mystified my entire life to the cause of that noise. At 3 miles distance, through the hedge of thousands of trees, that whine is distinct but sits in unnoticed level on most Saturdays. 

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July 1st, 2017 —  10:31am