This part is a kind of semiconductor called 2N5643.

Function of this product has NPN SILICON RF POWER TRANSISTOR.

Manufacturers : ASI

Image and pinout :

Some of the text within the PDF file :

2N5643 NPN SILICON RF POWER TRANSISTOR DESCRIPTION: The ASI 2N5643 is Designed for wideband large-signal amplifier stages in the 125 – 175 MHz range. PACKAGE STYLE .380 4L STUD .112x45° A B C E ØC FEATURES: • Minimum Gain = 7.6 dB • Output Power = 40 W • Omnigold™ Metalization System E B I J D H #8-32 UNC-2A G F E MAXIMUM RATINGS IC VCBO VCEO VEBO PDISS TJ TSTG θJC 5.0 A DIM MINIMUM inches / mm MAXIMUM inches / mm 65 V 35 V 4.0 V 60 W @ TC = 25 °C -65 °C to +200 °C -65 °C to +200 °C 2.9 °C/W A B C D E F G H I J .220 / 5.59 .980 / 24.89 .370 / 9.40 .004 / 0.10 .320 / 8.13 .100 / 2.54 .450 / 11.43 .090 / 2.29 .155 / 3.94 .230 / 5.84 .385 / 9.78 .007 / 0.18 .330 / 8.38 .130 / 3.30 .490 / 12.45 .100 / 2.54 .175 / 4.45 .750 / 19.05 CHARACT [ ... ]

2N5643 PDF Datasheet Download