5.1.2 Setting of period of channel A:
The signal of channel A can also be set and displayed in the form of period. Press the key of (option 1) and
select “CHA Period”. The present period value will be changed to green. Then use the number keys or the
knob to enter the period value. But frequency synthesizing way is still used within the generator. Limited by
the low-end resolution of frequency, only those frequency points with large distant period can be entered for
longer periods. Although the setting and display of the period are accurate, the period values of real output
signal will be greatly different. The user should know fairly well.
5.1.3 Setting of amplitude of channel A:
Press the key of (option 2) and select “CHA Ampl”. The present amplitude value will be changed to green.
Then use the number keys or the knob to enter the amplitude value. The amplitude will be output at the end
of “output A”. There are two ways for the amplitude of channel A. One is Vpp way and the other is Vrms
way. Press the unit key of (Vpp) or (mVpp) after data entering, the effective amplitude value can be entered
and displayed. Press the two unit keys directly without entering data, the display can be changed from one
unit to another.
Although there are two formats for amplitude values, the working way inside the generator is Vpp. Limited by
the amplitude resolution, a little difference will be produced between the former and the latter after
exchanging. Entering 1Vpp for sine wave, for example, the virtual value after changing is 0.353Vrms. But
entering virtual value of 0.353Vrms, the Vpp after changing is 0.998Vpp. Of course, the difference is within
the error range. If the waveform is square, the conversion coefficient is 2. For pulse, only Vpp but not virtual
value will be used.
5.1.4 Amplitude attenuation of channel A:
Press the key of (Option 2) and select “CHA Atten”. The present attenuation value will be changed to green.
Then use the number keys or the knob to enter the attenuation value. There are five levels of 0dB, 20 dB,
40dB, 60dB and Auto. The generator is set to “Auto” when startup. Then the generator selects the
attenuation proportion automatically according to the magnitude of the set amplitude. The attenuation
switches when the output amplitudes are 2Vpp, 0.2Vpp and 0.02Vpp. In this way, higher amplitude
resolution and signal-to-noise can be obtained regardless of the magnitude of amplitude. The distortion of
waveform is smaller. But a little jumping will occur for output signal when attenuation switching, which is not
allowed in some cases. So the fixed attenuation way is set for the generator. The
attenuation value can be entered using the number keys. The attenuation is 0dB for the entered data<20,
20dB for the entered data
≥
20, 40dB for the entered data
≥
40, 60dB for the entered data
≥
6 and auto for the
entered data
≥
80. The knob can also be used to adjust the attenuation. The attenuation will change a time for
each step. If the fixed attenuation way is selected, the attenuation step will not be changed when the
amplitude of signal changes So that the output signal within the whole amplitude range will be changed
continually. But if the amplitude of signal is small in the attenuation of 0dB, the distortion of waveform will be
larger and the signal-to-noise ratio is worse.
5.1.5 Output load:
The setting value of amplitude is calibrated when the output end is open. The real voltage of output load is
the setting value of amplitude multiplied by the assignment ratio of load resistance and output resistance.
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