UNI-T UTG9000C-II Series, Руководство пользователя

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When start frequency < stop frequency, sweep from low frequency to high
frequency.
When start frequency > stop frequency, sweep from high frequency to low
frequency.
When start frequency = stop frequency, outputs fixed frequency.
By default, the start frequency is 1kHz and the stop frequency is 1MHz,
but the range of start and stop frequency can vary with frequency sweep
waveform. See table 4-3 below for the frequency range of each frequency
sweep wave:
Table 4-3:
Frequency
UTG9002C-II UTG9005C-II
Min
1μHz
1μHz
1μHz
1μHz
Max
2MHz
2MHz
200kHz
1MHz
Min
1μHz
1μHz
1μHz
1μHz
Max
5MHz
5MHz
200kHz
1MHz
Carrier waveform
Sine wave
Square wave
Ramp wave
Arbitrary wave
4.2.3 Frequency Sweep Mode
Press Mode and use the key to move the cursor to Log (logarithmic
frequency sweep) or Line (linear frequency sweep):
Linear frequency sweep: waveform generator changes output frequency in
a linear way during frequency sweep;
Logarithmic frequency sweep: waveform generator changes output frequency
in a logarithmic way.
4.2.4 Frequency Sweep Time
After the frequency sweep function is enabled, the default frequency sweep
time (range of 1ms ~ 500s) is 1s. To change it, when the MOD modulation
is selected, press
to move the cursor to Time and press OK , then enter
the required value and select the unit, press OK again to confirm.
Picture 4-18 Set frequency sweep time
4.2.5 Select Trigger Source
The signal generator generates a frequency sweep output upon receiving a
trigger signal and then waits for the next trigger signal. The trigger source
of frequency sweep can be internal or external, which can be switched by
pressing the key when MOD modulation is selected.
1) Internal trigger: waveform generator will output a continuous frequency
sweep, the rate of which is determined by frequency sweep time.
2) External trigger: waveform generator is triggered by the TTL level signal
input from the external modulation interface.
4.2.6 Comprehensive Example
First make the instrument run in frequency sweep mode, and then set a pulse
wave signal with amplitude of 1Vpp and duty ratio of 50% as frequency sweep
wave. The frequency sweep mode is linear. Set starting frequency to be 1kHz,
stop frequency to be 50kHz, frequency sweep time to be 2ms, and use the
internal source to trigger and output the frequency sweep wave. The specific
steps are as follows:
UTG9000C-II User Manual