Reference PDF of 176 KB for the 2SA1425 transistor, carrying no information in its name beyond the part number. Under JIS designation rules, 2SA indicates a PNP transistor of the high-frequency class. The document most likely lists ratings, electrical characteristics and lead configuration, which are handy for diode-mode testing on the bench and for sourcing an equivalent. Verify the package and marking of the fitted part first, since small-signal transistors with similar codes can use different pin orders.
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.