ระบบ U777D

https://www.scribd.com/document/837244884/%E0%B8%97%E0%B8%B3%E0%B9%84%E0%B8%A1-U777D-%E0%B8%96%E0%B8%B7%E0%B8%AD%E0%B9%80%E0%B8%9B-%E0%B8%99%E0%B8%84%E0%B8%B2%E0%B8%AA%E0%B8%B4%E0%B9%82%E0%B8%99%E0%B8%84%E0%B8%A3%E0%B8%9A%E0%B8%A7%E0%B8%87%E0%B8%88%E0%B8%A3%E0%B8%97%E0%B8%B5-%E0%B8%94%E0%B8%B5%E0%B8%97%E0%B8%B5-%E0%B8%AA%E0%B8%B8%E0%B8%94%E0%B9%83%E0%B8%99%E0%B8%A2%E0%B8%B8%E0%B8%84%E0%B8%99%E0%B8%B5-170530

ระบบ U777D