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FNIRSI 138 PRO Key Features:
- High Precision Signal Analysis: With a real-time sampling rate of 2.5MSa/s and a 200KHz bandwidth, experience flawless signal scrutiny.
- Versatile Triggering Functions: Comprehensive trigger modes including single, normal, and automatic settings.
- Versatile Signal Compatibility: Designed to impeccably analyze both periodic analogue signals and aperiodic digital signals.
- High Voltage Measurement: Capable of gauging voltages up to an impressive ±400V.
- One-Key Auto Feature: Say goodbye to tedious adjustments. With just a press of the ‘AUTO’ button, the oscilloscope instantly displays the measured waveform.
- Crystal Clear Display: Flaunts a 2.4-inch high-definition LCD screen, ensuring clarity with a 320*240 resolution.
- Long-Lasting Battery Life: Powered by a built-in 1000mah high-grade lithium battery, the FNIRSI-138 PRO promises about 5 hours of continuous operation on a single charge(model with battery)
Why Choose the FNIRSI-138 PRO? Whether you’re a student embarking on an educational journey in R&D or a professional seeking a reliable tool for maintenance tasks, the FNIRSI-138 PRO Handheld Digital Oscilloscope promises unparalleled efficiency. Available now at Kunkune, the UK’s premium electronic supply destination.
Upgrade your toolkit and redefine precision with Kunkune’s FNIRSI-138 PRO Handheld Digital Oscilloscope. Secure yours today!
Troubleshooting for FNIRSI-138 PRO Handheld Digital Oscilloscope:
1：How can I tell if the battery is fully charged?
A: After the battery is fully charged, The charging light will change from red to green.
2:Why does the waveform jump up and down when testing the signal, Can’t see the waveform, just see multiple lines jumping up and down?
A: Set the trigger mode to “Auto” and then press the [AUTO] button once. If the problem is not solved, the clip on the probe may not be grounded, or the probe clip
end is open circuit. Please use a multimeter to check whether the probe is normal.
3: Why does the tested waveform shake from side to side, Can’t be fixed?
A: Need to adjust the trigger voltage, the yellow arrow on the right. Press the up and down keys in trigger mode, The trigger voltage can be adjusted. It is necessary to adjust the yellow indicator arrow to be between the upper and lower waveforms, The waveform is triggered. Also fixed.
4:Why is there no waveform when measuring a battery or other DC voltage?
A: The battery voltage signal is a stable DC signal, There is no curve waveform. In DC coupled mode, Then adjust the vertical sensitivity. There will be an upward or downward offset line waveform. If it is AC coupled, Then there is no waveform no matter how you adjust it.
5:Why when measuring the 220V waveform of the mains, The VPP peak-to-peak data below is more than 600 V instead of 220V or 310V?
A: Mains 220V is a symmetrical AC signal. The positive peak voltage (MAX) is +310V. The negative peak voltage (MIN) is -310V. So the peak-to-peak VPP below is 620V. The effective value (RMS) is often referred to as the 220V voltage. Mains voltage RMS fluctuates between 180~260V.
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So the peak-to-peak VPP is in the range of 507~733V.
6:Why is the measured mains 220V waveform, not a very standard sine wave?
Distortion occurs
A: The mains power grid is generally polluted, and contains more high-order harmonic components. The superposition of these harmonics on the sine wave will give a distorted sine. Generally, the mains waveform is distorted and has nothing to do with the oscilloscope itself.
7:Why is the position of the baseline (0V) and the left arrow (OV indication) different on the screen when there is no signal input, and there is a relatively large offset?
A: Please pull out the probe, and unplug the USB cable. Press the [AUTO] button to enter the calibration confirmation interface, Click the [OK] button to enter the automatic calibration
