projection plan position indicator

projection plan position indicator

[prə′jek·shən ′plan pə′zish·ən ′in·də‚kād·ər]
(electronics)
Unit in which the image of a 4-inch (10-centimeter) dark-trace cathode-ray tube is projected on a 24-inch (61-centimeter) horizontal plotting surface; the echoes appear as magenta-colored arcs on white background.