This part is a kind of semiconductor called STK0029.

Function of this product has HYBRID LINEAR IC.

Manufacturers : ETC

Image and pinout :

Some of the text within the PDF file :

v AMPLIFIER 25W MIN. AF POWER APPLICATION (D. P. P.) OUTPUT STAGE NAME sTK-0029 HYBRIDLINEARIC MODEL sx-580 TYPE E O U I V A L E N TC I R C U I T v ' PIN FUNCTION Pin No. 1 Function Input {-} Negativg power supply 2 I I I 3 4 Output NC , 5 6 7 8 I Output power supply Positive Input (+l NC 10 E E , o l [ ... ]

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