Covering the 1SV280 component, this 69.9 KB PDF appears in the schematics list but, given the 1SV prefix used for variable-capacitance diodes, most likely holds a datasheet. Read it for reverse voltage limits, the capacitance curve, series resistance and package details. Technicians use such information to check a suspect varactor in an oscillator or tuner and to confirm that a substitute will tune over the same range. Always compare marking code and package size with the original part.
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.