Documentation for the 1SV312 part in PDF form, roughly 72 KB and classed as a schematic. The 1SV numbering belongs to the JIS diode designations, a range Toshiba applies to varactor tuning diodes. The name lists only the part number. A technician reads it for the package outline and pin assignment. The capacitance-versus-voltage curve is the key figure when choosing a substitute, since a mismatch shifts the tuning range. Compare the marking code on the board part with the sheet before relying on it.
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.
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The standard format for schematics, block diagrams, power-sequence charts and service manuals.