Sized at 215 KB, this PDF documents the 2SA1428 transistor. Per JIS convention, 2SA numbers identify PNP transistors, nominally high-frequency types. No further detail such as maker, package or revision is given in the name. Inside you would normally find rating tables, typical characteristic graphs and a dimensioned outline. Repair use centres on confirming the pinout for in-circuit diode checks and selecting an equivalent with matching polarity, package and at least equal voltage and current ratings.
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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