PDF sheet for the 1SV160, catalogued as a schematic. The name adds V1, probably a document version, and sot323, the small three-lead SOT-323 surface-mount package. The 1SV prefix marks a JIS-registered diode, a series Toshiba uses for varactor tuning diodes. A technician reads it for the package drawing, pinout and capacitance-versus-reverse-voltage data when tracing a tuning or oscillator fault. SOT-323 parts are tiny, so check the marking code and pin orientation carefully under magnification before soldering.
The button opens the matching file on RM Schematics, or a source page if it is not catalogued there yet. The original attachment is from @cyberlanelectonik. Enginerys does not host this file.
How to open a .pdf file
The standard format for schematics, block diagrams, power-sequence charts and service manuals.