Light oscilloscope operating steps - Solutions - Huaqiang Electronic Network

Photocoupler

1. Choose the appropriate vibrator based on the following criteria:

• The operating frequency of the vibrator must be higher than the frequency of the signal being measured.
• The current output from the dynamic strain gauge should not exceed the maximum allowable current of the vibrator.
• The maximum amplitude of the measured signal should be less than the maximum linear amplitude of the vibrator.
• The impedance of the strain gauge should match the vibrator's impedance for optimal performance.

Once the correct vibrator is selected, it can be connected to the oscilloscope.

2. Perform a wiring check. Ensure all switches are in the off position and verify that all connections are properly made.

3. Turn on the power supply. When the motor starts, the power indicator light should illuminate, and the voltage reading should be approximately 5V. If this is not the case, adjust the power switch to a suitable voltage between 200 and 240V, then allow the oscilloscope to warm up for 30 minutes before proceeding.

4. Press the illumination button to activate the high-pressure mercury lamp. Let it burn for about 5 minutes, then open the spot grid and the grating. Observe the small light spots on the screen. If no spot appears, use the special tool to adjust the angle of the vibrator until the spot is visible on the screen.

5. Check if the dynamic resistance strain gauge’s resistance and capacitance balance are correctly set. Adjust the external critical resistance of the oscilloscope to an appropriate value.

6. Based on the primary and secondary frequencies, as well as the size and direction of the signal, position the light spot accordingly. Once the spot is in the desired location, secure the vibration mechanism to keep it fixed.

7. Estimate the amplitude of the signal on each channel and adjust the attenuation switch or sensitivity setting of the strain gauge so that the recorded signal remains within the measurement range.

8. Select the appropriate paper feed speed and time scale according to the frequency and rate of change of the signal. The faster the signal frequency, the higher the required speed. Some oscilloscopes have a labeled paper speed linkage system, which automatically adjusts the time scale when a speed is chosen.

9. Record the calibration strain values for reference.

10. Press and lock the “motor button” to start the rotation. Adjust the “shooting fixed length knob” to the desired recording length, press and lock the “shoot button,” and the oscilloscope will record the waveform automatically and stop once the preset length is reached.

11. After the recording is complete, remove the paper and expose it to fluorescent light or general indoor lighting for 5–50 seconds to reveal the waveform. Then wrap the black paper and store it properly. Finally, return all oscilloscope switches to their original stop positions.