The IRF840PBF is a 500V 8A 125W TO220AB Package Third generation power MOSFETs from Vishay provide the designer with the best combination of fast switching, low on-resistance and cost-effectiveness.
The BC547 is a NPN transistor hence the collector and emitter will be left open (Reverse biased) when the base pin is held at ground and will be closed (Forward biased) when a signal is provided to base pin.
The 2SK1937-01, 2SK-1937, K1937, 1937 is a 500V 15A 125W N-Channel Power MOSFET, High Speed Switching - Low On-Resistance - No Secondary Breakdown - Low Driving Power - High Voltage - VGS = ± 30V
The CD4026B- and CD4033B-series types are supplied in 16-lead dual-in-line plastic packages (E suffix), 16-lead small-outline packages (NSR suffix), and 16-lead thin shrink small-outline packages (PW and PWR suffixes).
The 2SC4835, 2SC-4835, 4835 is a 10V 80mA 150mW Silicon NPN Epitaxial Planer Type For UHF Band Low-Noise Amplification Transistor. Manufactured By NEC Semiconductor.
These epitaxial planar transistors are mounted in the TO-126 plastic package. The PNP types are the BD136 and BD140, and the complementary NPN types are the BD135 and BD139.