Portable oscilloscope Fnirsi DSO-TC4 3-in-1, 100 MHz bandwidth, handheld multimeter and waveform generator

FNIRSI DSO-TC4 is a portable 3-in-1 instrument that combines a digital oscilloscope, an electronic component tester and a signal generator. The device is intended for waveform analysis, component identification and signal simulation in service and diagnostics tasks. An intelligent Anti-Burn protection helps prevent damage to the input circuit when probes are connected incorrectly, and a 2.8-inch TFT color screen displays measurements and graphs for straightforward inspection.

Advantages

The instrument provides an analog bandwidth up to 10 MHz and a real-time sampling rate of 48 MSa/s, enabling detailed waveform capture. The integrated component tester automatically recognises diodes, transistors (including MOSFETs), resistors, capacitors and other passive and active components. A built-in signal generator offers 13 waveform types with frequencies from 0 to 50 kHz and amplitude control. USB-C charging and data transfer, a 1,500 mAh lithium-ion battery and multilingual interface (8 languages) support convenient portable operation.

Suitable for

• Field service diagnostics of electronic circuits
• Component testing and quick identification of semiconductors and passives
• Generating test signals for circuit verification and troubleshooting
• Educational use and basic laboratory measurements

Key specifications

• Display: 2.8-inch TFT color screen with adjustable brightness
• Analog bandwidth: 10 MHz
• Real-time sampling rate: 48 MSa/s
• Input impedance: 1 MΩ
• Coupling modes: AC / DC
• Vertical sensitivity (X1 range): 10 mV/div – 10 V/div
• Time base range: 50 ns – 20 s
• Trigger modes: Auto / Normal / Single; trigger types: rising edge, falling edge
• Automatic measurements: Max, Min, Average, RMS, Vpp, Frequency, Period, Duty cycle
• Signal generator: 13 waveform types, frequency 0–50 kHz, amplitude 0.1–3.0 V, fill factor 0–100%
• Component tester ranges: resistors 0.01 Ω – 50 MΩ; capacitors 25 pF – 100 mF; inductors 10 µH – 1000 µH; Zener diodes 0.01–32 V; diode forward drop <5 V
• Test voltage range: Probe X1 up to 80 Vpp (±40 V); Probe X10 up to 800 Vpp (±400 V)
• Battery: Lithium-ion 3.7 V, 1500 mAh; power via USB Type-C (5 V/1 A)
• Dimensions: approx. 90 × 142 × 27.5 mm; Weight: 186 g

How to use

Connect the appropriate probe to the input and select the required coupling (AC or DC) and vertical sensitivity. Use the time base and trigger controls to stabilise the waveform on the 2.8-inch screen; automatic measurement functions provide common parameters such as Vpp, frequency and RMS. For component testing, insert the component into the test socket or apply the test clips and follow the on-screen prompts for automatic identification and parameter readout. To generate test signals, choose a waveform type, set frequency, amplitude and fill factor, then connect the generator output to the circuit under test. Charge the device via the USB-C port and note that automatic sleep mode helps extend battery life between uses.

Recommendations

Use the Anti-Burn protection as intended and verify probe selection (X1/X10) before measuring high-voltage signals. When testing components, observe polarity for diodes and transistors and ensure the device is charged to avoid interrupted measurements.