2N1556 Bipolar Transistor

• Type: PNP
• Collector-Emitter Voltage, max: -50 V
• Collector-Base Voltage, max: -100 V
• Emitter-Base Voltage, max: -50 V
• Collector Current − Continuous, max: -15 A
• Collector Dissipation: 106 W
• DC Current Gain (h_fe): 30 to 60
• Operating and Storage Junction Temperature Range: -65 to +110 °C
• Package: TO-3

Here is an image showing the pin diagram of this transistor.You can replace the 2N1556 with the 2N4399, 2N5683, 2N5683G, 2N5684, 2N5684G, 2N5745, 2N5879, 2N5880, 2N5883, 2N5883G, 2N5884, 2N5884G, 2N6029, 2N6246, 2N6247, 2N6248, 2N6436, 2N6437, 2SA907, BD316, BD318, MJ14001, MJ14001G, MJ14003, MJ14003G, MJ2955, MJ2955A, MJ2955G, MJ4502, MJ4502G, NTE180 or NTE219.