Television Transistors: Estimated Prices in Nairobi for TV Repair

Transistors are semiconductor devices used for switching and amplification in television circuits. In TV power supply boards, power transistors (including MOSFETs and bipolar junction transistors) handle high-current switching in the SMPS circuit. In audio sections, transistors amplify audio signals. When a power transistor fails (commonly a short-…

Transistors are semiconductor devices used for switching and amplification in television circuits. In TV power supply boards, power transistors (including MOSFETs and bipolar junction transistors) handle high-current switching in the SMPS circuit. In audio sections, transistors amplify audio signals. When a power transistor fails (commonly a short-circuit failure caused by a power surge), it often takes out other nearby components — including fuses and resistors — making diagnosis important before ordering parts.

Types found in TVs: The most common are NPN/PNP BJTs (e.g. 2SC, 2SA series), N-channel and P-channel MOSFETs, and IGBT transistors in larger high-power circuits. Nairobi's Nerokas and River Road component shops stock a range of common types.

Transistor Type	Common Part Numbers	Estimated Price (per unit)
Small-signal BJT (NPN/PNP)	BC547, 2N2222, 2N3904	KSh 15 – 50
Medium-power BJT	TIP31, TIP41, MJE340	KSh 30 – 120
Power MOSFET (N-channel)	IRF840, FQP8N60, K2961	KSh 80 – 350
Power MOSFET (P-channel, switching)	IRF9540, FQP17P06	KSh 80 – 300
Darlington transistor	TIP122, TIP142	KSh 50 – 150
SMD transistor pack (assorted)	Various	KSh 150 – 600

Note: Power transistors in the SMPS section are among the most surge-vulnerable components in a TV. When a power transistor fails, always check the gate resistor and fuse — they often fail together.