This part is a kind of semiconductor called BF980A.
Function of this product has Silicon N-Channel Dual Gate MOS-FET.
Manufacturers : Signetics
Image and pinout :

Some of the text within the PDF file :
DataShee DataSheet 4 U .com etcom DataShee DataSheet 4 U .com DataSheet 4 U .com etcom DataShee etcom DataShee DataSheet 4 U .com etcom DataShee DataSheet 4 U .com DataSheet 4 U .com [ ... ]
BF980A PDF Datasheet Download
