TFG6800 Series Function/Arbitrary Waveform Generator Users’ Guide
Suin Instruments Co., Ltd
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its parameter.
3.3.3 Frequency Deviation
: Press
〖
FreqDev
〗
to set frequency deviation value. It means the carrier
frequency’s variation quantity when modulation signal reaches in full amplitude during the
frequency modulation. In modulation signal’s positive full value, output frequency is carrier
frequency plus frequency deviation. While in its negative full value, output frequency is that
carrier frequency decreases frequency deviation. Thus, frequency deviation should conform to the
following two conditions:
(carrier frequency-frequency deviation)>0
(carrier fre frequency deviation)<frequency upper limitation
frequency deviation ≤ carrier frequency/2
3.3.4 Modulation frequency
: Press
〖
ModFreq
〗
to set modulation signal’s frequency value. In
usual modulation frequency is lower than carrier frequency.
3.3.5 Modulation waveform
: Most of the built-in waveforms could be used as modulation
waveform, but some may be not suitable. Press
〖
Shape
〗
to choose modulation signal’s waveform.
3.3.6 Modulation source
: Press
〖
Source
〗
to choose the modulation source. If ‘Internal’ is chosen,
instrument will use internal modulation source, at this time modulation frequency and modulation
waveform’s setting is effective. If ‘External’ is chosen, instrument will use external modulation
source, at this time modulation frequency and modulation waveform’s setting will be ignored.
Input modulation signal from rear panel’s
《
Modulate In
》
port in present channel. When external
modulation signal’s amplitude is 5Vpp, DC offset is 0Vdc, frequency deviation display will match
with the actual frequency deviation.
3.3.7 Sync output
: Sync signal’s duty cycle is 50%, sync signal’s frequency is equal to
modulation frequency, sync signal’s phase takes modulation signal’s phase as reference.
3.4 Amplitude Modulation
In amplitude modulation, carrier’s amplitude changes with the modulation signal’s transient
voltage.
3.4.1 Function selection
: Press
【
Modulate
】
to enter modulation function, then press
〖
Modulation
Type
〗
to display modulation type menu, press
〖
AM
〗
, modulation type will be AM, and display the
