This image was acquired from
wikimedia. It was marked as Public Domain or CC0 and is free to use. To verify, go to the source and check the information there.
NRL's PPI radar display. en The PPI radar display as originated by NRL The PPI is now user worldwide in detection navigation air traffic control and object identification radar systems nrl navy mil US Naval Research Laboratory PDUSGov Plan position indicators
Page 2023 Free-images.com. All images are Public Domain