When overvoltage protection is generated, a warning symbol appears in the upper right corner of the instrument screen, blinks for three seconds and beeps. 

The channel output terminal is set with overvoltage protection, which is performed when one of the following conditions is met: Amplitude setting value > 625mVpp, input voltage >士12.5V I, frequency< 10kHz.

Amplitude setting value≤625mVpp, input voltage >士2.5V, frequency< 10kHz.

it can try to restore to factory setting at the same time.

The settable range of amplitude is limited by the setting of impedance and frequency/period, and the amplitude displayed on the screen is either the  default value or the previous setting.

What is the relation of amplitude and frequency？

UTG2000B series output impedance is 50Ω, the maximum sine wave is 10Vpp。The voltage decreases as the frequency increases. As shown in the figure below (refer to the datasheet)

How does impedance affect amplitude?

The output impedance setting affects the amplitude and DC offset. The BNC connector of  the signal source [CH1/CH2] has a series output impedance of 50 Ω. If the actual load is different from the set value, the displayed voltage amplitude will not match the voltage amplitude of the part under test. To ensure the correct voltage amplitude, it should make sure the load impedance setting matches the actual load.

For example, if the Amp is set to 5Vpp, and the output impedance is changed from "50Ω" to "high resistance", the amplitude displayed on the screen will be doubled to "10Vpp". On the contrary, if users change the output impedance from "high resistance" to "50Ω", the Amp will drop by half to 2.5Vpp. Note that only the display will be changed after the parameter modification, the actual output of the generator will not be changed.

As for UNI-T signal sources of various series such as UTG900E, UTG2000A, UTG2000B, UTG4000A, UTG9000T, when the output impedance is 50Ω，the maximum sine wave Vpp=10Vpp. When  the output impedance is high resistance, the maximum sine wave Vpp=20Vpp.  Voltage decreases as frequency increases. Please refer to the product manual for details.

Through the arbitrary waveform editor in the signal source of host computer, user can edit the desired arbitrary waveform file. Then load it to the signal source arbitrary waveform path via USB flash drive to output the edited arbitrary waveform.

Arbitrary waveform files which exceed 16k or whose table header does not match the source type cannot be stored in the signal source. 

1、Capture the complete waveform of the signal and perform calculations：

Is it possible to choose an analog acquisition card with 250KS/s sampling rate to display the required waveform?  

Not really. We have not yet considered the measurement accuracy of 0.1%.

Because the analog signal is the continous and the signal period is 1/(22.5K)=44.4us，duty cycle accuracy requires to be 0.1%, .signal resolution should be at least 44.4us/1000=44.4ns，and sampling rate should be larger than 1/44.4ns=22.5MS/s,  then we can get the waveform that meet the accuracy requirements. In case the waveform can be measured to meet the accuracy requirement.

2、Convert the analog signal into a digital signal and  use pulse counting to calculate its duty cycle:

Convert a 60V analogue pulse signal into a digital pulse signal and use pulse counting to measure the duty cycle of this signal.

 If the digital signal is a 0 or 1, this sampling requirement is different from the analogue sampling requirement.

Why will happen if set output impedance to "high impedance" and then reverts to 50Ohm after a while?  

This may happen because the user have changed the voltage units when setting the voltage value parameter. When the user selects dbm, it only corresponds to a 50Ω output impedance.

GND at the power input, GND at the output BNC (marked), the  two  terminal must be conductive (generally less than 100mΩ).  The maximum 42Vpk to GND refers to the safety specification at the BNC of the output. The peak voltage allowed here is 42Vpk, otherwise it may be damaged.The product output will not have a voltage exceeding this limit, but if there is another signal flow backward to this output BNC, there is a possibility of exceeding this limit, and if the limit is exceeded, the machine will be damaged. For example, if a 50V signal is accidentally added to the BNC position of this output, the signal source may be damaged.

Frequency precision：The ratio of the output frequency and the setting frequency of the signal generator.

(output frequency - output frequency (Hz) x aging rate (ppm/year) x time since last calibration) / output frequency

Amplitude precision：The ratio of the output amplitude and the setting amplitude of the signal generator.

Flatness：The change in amplitude when switching from one frequency to another is called flatness. （1kHz is used as a typical value for comparison）

The smaller the change in amplitude from one frequency to another, the flatter the output.

If the generator still remains blank screen when power on.

1) Check whether the power supply is connected properly.

2) Check whether the power switch on the rear panel is set to "I".

3) Check whether the power switch on the front panel is connected .

4) Restart the instrument.

5) If the instrument still can't work normally, please contact your UNI-T dealer or local offices for support.

Correct settings but no waveform output

1) Check whether the BNC cable is properly connected to the channel output.

2) Check whether the key CH1 or CH2 is turned on.

3) Save the current settings of the instrument to a USB flash drive and "restore factory settings",  then restart the instrument.

4) If the instrument still can't work normally, please contact your UNI-T dealer or local offices for support.

1) Check whether the USB flash drive device is working properly.

2) Make sure you are using Flash type USB flash drive device, this instrument does not support hard disk type USB flash drive device.

3) Restart the instrument and insert the USB flash drive again to see if it works properly.

4) If the USB flash drive still can not be recognized, please contact UNI-T dealer or local office and let us serve you.

(1) General Maintenance 

Do not store or put the instrument under direct sunlight for a long time, especially the LCD display panel. Caution:  Sprays, liquids or solvents are not allowed for the instrument or probe  to avoid damage to the instrument or the probe. 

(2) Cleaning 

Check the instrument and probe frequently according to the operating conditions. Fellow the steps to clean the surfaces of the instrument.

Please use a soft cloth to wipe dust on the surface of the instrument and probe. When cleaning the LCD panel, be careful not to scratch the transparent protective film. 

Power off the instrument first and wipe the instrument with a soft cloth.Use a mild detergent or water to clean if necessary.

Do not use any abrasive chemical cleaners as they may damage the instrument or the probe. 

Warning: Make sure the instrument is completely dry before rebooting. Moisture may cause electrical short-circuit or even personal injury!