This part is a kind of semiconductor called BF494.

Function of this product has NPN RF Transistor.

Manufacturers : Fairchild Semiconductor

Image and pinout :

Some of the text within the PDF file :

BF494 NPN RF Transistor July 2006 BF494 NPN RF Transistor tm TO-92 1. Collector 2. Emitter 3. Base Ta = 25°C unless otherwise noted Absolute Maximum Ratings * Symbol VCEO VCBO VEBO IC TJ TSTG Collector-Emitter Voltage Collector-Base Voltage Emitter-Base Voltage Collector Current - Continuous Junction Temperature Storage Temperature Range Parameter Value 20 30 5.0 30 150 - 55 ~ 150 Unit V V V mA °C °C * These ratings are limiting values above which the serviceability of any semiconductor device may be impaired. NOTES: 1) These ratings are based on a maximum junction temperature of 150 degrees C. 2) These are steady state limits. The factory should be consulted on applications involving pulsed or low duty cycle operations Thermal Characteristics Symbol PD Rθ [ ... ]

BF494 PDF Datasheet Download