2N4126 Bipolar Transistor

• Type: PNP
• Collector-Emitter Voltage, max: -25 V
• Collector-Base Voltage, max: -25 V
• Emitter-Base Voltage, max: -4 V
• Collector Current − Continuous, max: -0.2 A
• Collector Dissipation: 0.625 W
• DC Current Gain (h_fe): 120 to 360
• Transition Frequency, min: 250 MHz
• Noise Figure, max: 4 dB
• Operating and Storage Junction Temperature Range: -55 to +150 °C
• Package: TO-92
• Electrically Similar to the Popular MPS4126 transistor

The 2N4126 is manufactured in a plastic TO-92 case. When looking at the flat side with the leads pointed downward, the three leads emerging from the transistor are, from left to right, the emitter, base, and collector leads.
Here is an image showing the pin diagram of this transistor.The BC858 (SOT-23), BC858W (SOT-323), BC859 (SOT-23), BC859W (SOT-323), MMBT4126 (SOT-23) and MMST4126 (SOT-323) is the SMD version of the 2N4126 transistor. These transistors are of the same type, have similar parameters and are designed for surface mounting.The MPS4126 is the TO-92 version of the 2N4126.You can replace the 2N4126 with the 2SA642, 2SB564A, BCX79, KSA642, KSB564A, MPS4126, MPS6535, MPS6651, MPS6651G, MPS6652, MPS6652G, MPS750, MPS750G, MPSW51, MPSW51A, MPSW51AG, MPSW51G or PN200.