but this changed in the late 1880s, because now in addition to local trains, national and even international long-distance trains used the line. the system has been tested on over 70 adults (data presented at clinical meetings). the type 293 radar was designed as a short-range aerial-search radar for surface ships in 1945. it used the same transmitter as the type 277 surface-search radar, but used a new antenna design intended to cover the area above the ship to provide air warning instead of surface search. 