FNIRSI DSO-TC3 3-in-1 Digital Oscilloscope, Transistor Tester, and Signal Generator

1. Introduction

The FNIRSI DSO-TC3 is a versatile 3-in-1 electronic measuring instrument that skillfully integrates a digital oscilloscope, an electronic component tester, and a signal generator. It also includes additional functions such as continuity testing, voltage testing, temperature and humidity measurement, and infrared decoding. Designed for portability and ease of use, the device features a 2.4-inch color TFT display and a built-in rechargeable lithium battery, offering powerful and practical functionalities for various applications.

This manual provides detailed instructions on how to use the product, important precautions, and related information to ensure optimal performance. Please read it thoroughly before operating the device.

2. Safety Precautions

• Do not use the instrument in flammable and explosive environments.
• When measuring high voltage, do not touch any metal part of the oscilloscope to avoid the risk of electric shock.
• Avoid performing high voltage tests while the device is charging.
• Do not place the machine in an unstable location or where it may be subject to strong vibrations.
• Do not place the machine in areas with high humidity, dust, direct sunlight, outdoors, or near heat sources.
• The external circuit must be powered off during calibration to prevent instrument damage.
• The used batteries and discarded instruments should not be disposed of with household waste. Please follow national or local laws and regulations for proper disposal.

3. Setup

3.1 Package Contents

The FNIRSI DSO-TC3 comes in two main configurations: Standard and Option. Please verify your package contents against the list below.

NO.1 (Standard)

• DSO-TC3 unit ×1
• Ordinary probe ×1
• Test hook ×3
• Type-C charging cable ×1
• Packing box ×1
• Manual ×1

NO.2 (Option)

• DSO-TC3 unit ×1
• P6100 High Voltage Probe ×1
• Ordinary probe ×1
• Test hook ×3
• Adapter ×1
• Type-C charging cable ×1
• Packing box ×1
• Manual ×1

3.2 Device Overview and Key Interface

The DSO-TC3 features a compact design with clearly labeled buttons and connection ports.

Buttons and Navigation

The device is operated using a set of intuitive buttons:

Test Sockets

The device features a 14-hole double-row test socket with a locking mechanism, located at the bottom left of the screen. Each socket is marked 1, 2, 3, K, A. Sockets with the same label are internally short-circuited. A small lever on the left end of the socket allows for relaxing (up) or locking (down) the connections.

The K-A-A jack is a specialized area for withstand voltage testing, providing a DC high voltage of approximately 30V or more. K is positive and A is negative. Do not mix connections. For Zener diodes, insert the anode into A and the cathode into K.

Signal Interface

Three MCX coaxial sockets are evenly distributed on the top surface. Their outer rings are connected to a common ground. They serve different purposes:

• IN (0~40V): Test voltage input port. The core wire is positive. Maximum measured voltage cannot exceed DC40V.
• DDS: Signal generator output port. Outputs five waveform signals with adjustable pulse width.
• DSO: Oscilloscope test signal input port. Maximum input voltage cannot exceed 40Vpk.

Important: When connecting test lines, always use MCX plug test lines with the instrument.

3.3 Charging

The instrument is powered by a built-in large-capacity lithium battery. A USB Type-C charging port is located on the bottom surface for connection to a 5V charger.

• During charging, the indicator light is always red.
• When fully charged, the indicator light turns green.

4. Operating Instructions

4.1 Power On/Off

To power on the device, short press the Back/Power button. To power off, long press the Back/Power button.

4.2 Home Screen and Function Selection

Upon powering on, the device displays a home screen with four main options: M-Tester (Transistor Tester), Oscilloscope, Generator, and Tools. Use the left and right navigation keys to switch between these functions. Press the OK/Menu button to enter the selected function.

4.3 Oscilloscope Mode

The oscilloscope function allows for real-time waveform analysis. Key features include:

• Display: 2.4" TFT (320x240)
• Bandwidth: 500KHz
• Sampling Rate: 10MSa/s
• Trigger: Auto / Normal / Single
• Voltage Range: 1x ±40V / 10x ±400V
• Coupling: AC/DC
• Input Resistance: 1MΩ
• Vertical Sensitivity: 10mV to 10V
• Horizontal Time Base Range: 1uS to 10s
• Battery: 1500mAh, providing approximately 4 hours of work time.

To enter Oscilloscope mode, select 'Oscilloscope' from the home screen and press OK/Menu. The screen will display the waveform. Parameters at the bottom and upper left corners can be selected using left/right keys and adjusted with up/down keys. Long press the Left/Run button to stop/run the waveform.

Real-time Measurement Parameters

Long press the Right/Hold button to show/hide the following 8 real-time measurement parameters:

Oscilloscope Probe Usage

Insert the oscilloscope probe with an MCX plug into the [DSO] jack. Adjust the attenuation gear on the probe, then connect the ground clip to the reference ground of the circuit. Connect the probe tip or hook to the measured node to observe the voltage waveform.

Important: The probe attenuation factor must match the measured signal voltage. Do not measure signals exceeding the maximum range. When measuring signals above safe voltage, avoid touching exposed metal parts of the instrument.

4.4 Transistor Tester Mode (M-Tester)

The M-Tester automatically identifies and measures various transistors (NPN/PNP triodes, N/P-channel MOSFETs, JFETs, diodes, dual diodes, thyristors) and passive components (resistors, inductors, capacitors).

Using the 1-2-3 Test Area

Insert the component's pins into the appropriate holes (1, 2, or 3) in any order. Lock the socket, then press the OK/Menu button to start the test. The device will automatically identify the component and display its pinout and parameters.

• Detects internal protective diodes in bipolar transistors and MOSFETs.
• Measures current amplification factor (hFE) and emitter junction voltage for bipolar transistors.
• Identifies Darlington transistors by high threshold voltage and current amplification.
• Displays triode parameters only when measurement is valid.
• Equivalent capacitance and reverse leakage current of diodes are displayed only when valid.
• FET turn-on/off voltage must be less than 5V for proper measurement; otherwise, only equivalent parameters are shown.
• Thyristor turn-on voltage must be less than 5V, and trigger current for conduction less than 6mA.

Important: Always discharge capacitors before measuring to prevent damage to the instrument. It is not recommended to test components online or live.

Using the K-A-A Test Area

This area is for withstand voltage testing. Insert the positive lead of the component (e.g., Zener diode anode) into A and the negative lead (cathode) into K. Lock the socket and press OK/Menu to start. The maximum measurement range for regulated diodes is 24V.

4.5 Signal Generator Mode

The signal generator can produce 6 types of waveforms with adjustable frequency and amplitude. To enter this mode, select 'Generator' from the home screen and press OK/Menu.

Available Waveforms:

• Sine wave
• Square wave
• Pulse wave
• Triangle wave
• Ramp
• DC

Use the up/down keys to select the waveform. Short press the Right/Hold key to change frequency or amplitude, then use the up/down keys to adjust the value. Short press the Left/Run key to exit. The frequency upper limit is 10KHz, and the amplitude is capped at 3.3V.

4.6 Toolbox Functions

The 'Tools' section offers several utility functions. Select 'Tools' from the home screen and press OK/Menu to access them.

Available Tools:

• Continuity Test: Use any two corners of the 1-2-3 test socket. If the circuit has low resistance, it's considered 'connected' and a buzzer will sound.
• Voltage Test: Insert MCX test lines into the [IN (0~40V)] jack to detect voltage.
• DS18B20 Digital Temperature Test: Follow screen prompts to insert the DS18B20 sensor into the test socket.
• DHT11 Temperature and Humidity Test: Follow screen prompts to insert the DHT11 sensor into the test socket (do not connect the third pin).
• Infrared Decoding: Point an infrared remote control at the 'IR' mark on the device panel and press a button. The instrument will decode the signal and display the user code, data code, and corresponding infrared waveform.
• Automatic Calibration: Insert a three-pin short wire into the 1-2-3 test socket. Follow prompts to disconnect wires during calibration. Wait for the progress bar to reach 100%.

5. Specifications

5.1 General Specifications

5.2 Digital Oscilloscope Specifications

5.3 Component Test Mode Specifications

5.4 Signal Generator Specifications

6. Maintenance

6.1 Battery Care

• Upon receiving the device, ensure it is fully charged before first use.
• For prolonged storage, discharge the battery to 3.7V.
• Perform a charge-discharge cycle every quarter to maintain battery health.
• Always use a 5V power adapter for charging.

6.2 Firmware Upgrade

To upgrade the firmware, connect the device to a computer via USB. Open the upgrade software on your computer. While pressing the Down key on the device, press the Power button to enter the upgrade page. Select the corresponding firmware in the software to complete the upgrade.

7. Troubleshooting

7.1 Common Issues and Solutions

• Q: How to tell if the battery is fully charged?
  A: The charging indicator light will change from red to green when fully charged.
• Q: Why does the test waveform keep shaking and cannot be fixed?
  A: The trigger voltage needs adjustment. The yellow arrow on the right side of the screen indicates the trigger voltage. In trigger mode, use the up and down keys to adjust this voltage. Position the yellow indicator arrow between the upper and lower limits of the waveform to stabilize it.
• Q: Why is there no waveform when measuring a battery or other DC voltage?
  A: A battery or DC voltage signal is stable and does not produce a curved waveform. In DC coupling mode, adjusting the vertical sensitivity will show an upward or downward offset straight line. In AC coupling mode, no waveform will be displayed regardless of adjustments.
• Q: Why is the measured 220V mains waveform not a standard sine wave and appears distorted?
  A: Mains power grids often contain higher-order harmonic components due to pollution. These harmonics superimpose on the sine wave, causing a distorted waveform. This is a normal phenomenon and not an issue with the oscilloscope itself.
• Q: Why are only diode and capacitance parameters obtained when measuring MOSFETs and IGBTs?
  A: If the turn-on or turn-off voltage of the MOSFET or IGBT exceeds 5V (the maximum supply voltage of the chip), they cannot be turned on or off normally. In such cases, only their equivalent parameters (like diodes and capacitors) can be measured.
• Q: Is it a single channel device?
  A: Yes, the DSO-TC3 is a single-channel oscilloscope.

8. User Tips

• For accurate component testing, ensure proper contact in the test sockets. The locking mechanism helps secure components.
• When using the oscilloscope, always match the probe's attenuation setting (1X or 10X) with the device's setting for correct voltage readings.
• If you encounter any issues or have questions, contact FNIRSI customer service for assistance.

9. Warranty and Support

FNIRSI offers a commitment to customer satisfaction. Any user with questions or issues can contact FNIRSI for a satisfactory solution, along with an extra 6-month warranty.

Contact Information:

• Manufacturer: Shenzhen FNIRSI Technology Co.,LTD.
• Service Phone: 0755-83242477
• Business Email: fnirsiofficial@gmail.com
• Equipment Service Email: fnirsiofficialcs@gmail.com
• Website: www.fnirsi.cn
• Address: West of Building C, Weida Industrial Park, Dalang Street, Longhua District, Shenzhen, Guangdong, Mainland China
• Execution Standard: GB/T 15289-2013

A PDF version of the user manual is available for download. You can find it by scanning the QR code provided in the product packaging or by visiting the official FNIRSI website.