Bipolar Junction Transistor (BJT)

This transistor assortment kit includes a carefully selected range of popular NPN and PNP bipolar junction transistors (BJTs) in the TO-92 package, commonly used in analog circuits, switching applications, signal amplification, and general-purpose electronics.

Each transistor is labeled and individually selected for its versatility and reliable performance in DIY electronics, Arduino projects, prototyping, repairs, and educational labs. Whether you’re working on signal processing, audio circuits, or digital logic interfacing, this kit provides a robust foundation of general-purpose BJTs.

Available Transistors:

✅ NPN Transistors:

• BC337 – Medium current, general-purpose

• BC517 – Darlington pair, high gain, low current

• BC547 – Low-noise, low-current

• BC548 – General-purpose

• BC549 – Low-noise version of BC548

• BC550 – Ultra low noise, low voltage

✅ PNP Transistors:

• BC327 – Medium current, general-purpose

• BC556 – General-purpose PNP, audio applications

• BC557 – General-purpose PNP

• BC558 – Low-noise PNP, complementary to BC548

General Specifications:

• Package Type: TO-92

• Maximum Collector Current: 100mA to 800mA (varies by type)

• Maximum Collector-Emitter Voltage: 30V to 65V

• DC Current Gain (hFE): ~110 to 1000+ depending on transistor

• Power Dissipation: Up to 625mW

• Polarity: Mix of NPN and PNP types

• Applications: Signal amplification, switching, audio, interfacing, digital logic, hobby electronics

Applications:

• Signal amplification in analog circuits

• Switching and control circuits

• Audio pre-amplifier and tone control circuits

• Digital interfacing and logic conversion

• Educational experiments and prototyping

This BJT transistor set is perfect for electronics enthusiasts, educators, repair technicians, and developers looking to have essential, widely used transistors at hand for rapid circuit development and troubleshooting.