3-in-1 handheld unit: digital oscilloscope, electronic component tester, and PWM generator in one compact device. - 500 kHz bandwidth with real-time sampling; measures voltages up to 400 V. - PC online operation: supports connection to a PC for fast transistor pairing, identification of mixed surface-mount and through-hole components, and rapid screening of small component batches. Automatically identifies and measures NPN and PNP transistors, diodes, dual diodes, and other transistors. - Sine form PWM generator: five internal base waveform frequencies in the range 1 kHz to 10 kHz; output 0–3.3 V with 50% duty cycle. Oscilloscope vertical sensitivity from 10 mV to 10 V; horizontal timebase from 1 µs to 10 s; more waveform samples per unit time for higher accuracy. - TFT display: 2.4" high-resolution display with adjustable backlight for easy reading. Fully charged in 1–2 hours using a 5 V 2 A adapter; built-in 1500 mAh battery provides about 4 hours of operation. Indicators show charging status: green when charge is complete, red when charging. - Portable and practical: pocket-friendly handheld design suitable for fieldwork, repair, and development. - 3 practical use scenarios: - Rapid transistor matching and automatic component identification on PCBs during repair. - Quick screening of small component batches, including mixed surface-mount and through-hole parts. - On-site testing of PWM signals and waveform replication in power electronics and microcontroller projects.