Component datasheet for the 2SD1851 transistor, supplied as a 93.4 KB PDF and classed as a schematic in the index. 2SD numbers mark NPN bipolar transistors registered under the Japanese JIS scheme, often used in power supplies, drivers and audio stages. Use the figures for maximum voltage, current and gain to judge a replacement, and the outline drawing for the pin positions. Check the part print and any suffix letter on the old device, since it indicates gain grouping or package style.
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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