2N3724 Bipolar Transistor

• Type: NPN
• Collector-Emitter Voltage, max: 30 V
• Collector-Base Voltage, max: 50 V
• Emitter-Base Voltage, max: 6 V
• Collector Current − Continuous, max: 1.2 A
• Collector Dissipation: 3.5 W
• DC Current Gain (h_fe): 60 to 150
• Transition Frequency, min: 300 MHz
• Operating and Storage Junction Temperature Range: -65 to +200 °C
• Package: TO-39

Here is an image showing the pin diagram of this transistor.You can replace the 2N3724 with the 2N3725, 2N3725A, 2N5334, 2SC512 or 2SC512-O.