Brief 41.1 KB PDF for the 2SA921, with an _E suffix in the name that likely marks an English-language edition, though that is not certain. The 2SA prefix follows the Japanese JIS convention for PNP bipolar transistors, so this is a component datasheet rather than a board schematic, and no equipment model is given. Use it for pinout, ratings and package details when replacing the part, and double-check lead order on the physical case, because older through-hole transistors can use different pin arrangements from modern ones.
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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