This post explains for the transistor.
The Part Number is C4131, 2SC4131.
The function of this semiconductor is 50V, 15A, NPN Transistor.
The package is TO-3PF Type
Preview images :
The C4131 is 50V, 15A, Silicon NPN Epitaxial Planar Transistor.
The NPN transistor is used to amplify or switch electronic signals and is widely used in many electronic circuits. It works by controlling the current flow between the collector and emitter terminals through the base terminal.
When a small current is applied to the base, it controls a much larger current between the collector and emitter, making the NPN transistor an effective amplifier or switch.
Absolute maximum ratings ( Ta=25°C )
1. Collector to Base Voltage: Vcbo = 100 V
2. Collector to Emitter Voltage: Vceo = 50 V
3. Emitter to Base Voltage: Vebo = 15 V
4. Collector Current: Ic = 15 A
5. Collector Dissipation : Pc = 60 W ( Tc=25°C )
6. Junction Temperature: Tj = 150°C
7. Storage Temperature: Tsg = -55 ~ +150°C
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