PDF datasheet, 178 KB, for the 2SA1804 transistor. In Japanese JIS numbering a 2SA part is a PNP bipolar transistor, and this document should provide its voltage, current and power limits together with gain data and package dimensions. On the bench it helps with identifying a burnt component, checking junctions in diode mode and choosing a substitute with adequate ratings. Because lead order can vary between packages and makers, confirm the pinout against the footprint before installing anything.
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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