This part is a kind of semiconductor called BU508A.

Function of this product has NPN TRIPLE DIFFUSED PLANAR SILICON TRANSISTOR.

Manufacturers : Wing Shing Computer Components

Image and pinout :

Some of the text within the PDF file :

BU508A COLOR TV HORIZONTAL OUTPUT APPLICATIONS(No Damper Diode) ! ! High Collector-Base Voltage(VCBO=1500V) High Speed Switching NPN TRIPLE DIFFUSED PLANAR SILICON TRANSISTOR SC-65 ABSOLUTE MAXIMUM RATINGS (TA=25℃) Characteristic Collector-Base Voltage Collector-Emitter Voltage Emitter-Base voltage Collector Current (DC) Collector Dissipation (Tc=25℃) Junction Temperature Storage Temperature Symbol VCBO VCEO VEBO IC PC Tj Tstg Rating 1500 800 6 5 50 150 -50~150 Unit V V V A W ℃ ℃ ELECTRICAL CHARACTERISTICS (TA=25℃) Characteristic Collector- Emitter Cutoff Current(VBE=0) Collector Cutoff Current Emitter Cutoff Current DC Current Gain Collector- Emitter Saturation Voltage Symbol ICES ICBO IEBO hFE VCE(sat) Test Condition VCE=800V , RBE=0 VCB= 800 V , IE=0 VEB= 4V , IC=0 [ ... ]

BU508A PDF Datasheet Download