Ok lets say you have a passive contact on a target bearing 010 degrees. You want to use active to determine the range. Click on the display on bearing 010 so the line with the selector box is on that bearing (this is for reference.) select range scale as desired, normally 20,000 yards is the max but 40,000 could produce results on a large target. Select single ping and ping. Data will begin to flow in, looking like static. When you hear a ping return click on bearing 010 degrees where the data has just come in and press mark. If you get a contact entered you have located the range of the target, if not wait for another ping return (that return was of another contact not o the bearing of your target).
If you don't get a return on the bearing of your target, try increasing the range or marking to left or right of where you heard the return ping since the contact may have moved.
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