UNI-T UTG2122B, User Manual

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UTG2000B Series 47
Carrier Wave Frequency Setting
See Carrier Wave Frequency Setting
Modulation Source Selection
The device can select internal modulation source or external modulation source. After enabling ASK
function, the default of modulation source is internal. If need to change, press Param
→
Source
→
External in turn.
1) Internal Source
When modulation source is internal, internal modulation wave is a square wave of 50% duty ratio
(not adjustable). The ASK rate can be set to customize modulated waveform amplitude hopping
frequency.
2) External Source
When modulation source is external, carrier waveform will be modulated by an external waveform.
ASK output amplitude is determined by the logic level of modulation interface (FSK Trig connector).
For example, output the carrier wave amplitude of current setting when external input logic is low,
and output currently set carrier wave amplitude, when input logic is high, output amplitude is less
than currently set carrier wave amplitude.
ASK Rate Setting
When modulation source is internal, frequency of ASK amplitude jump can be modulated. After
enabling ASK function, ASK rate can be set and the settable range is 2mHz to 1MHz, the default rate
is 100Hz. If need to change, press Param
→
Rate in turn.
Comprehensive Example
Make the instrument work in amplitude shift keying (ASK) mode, then set a logic signal with 300Hz
from the internal of the instrument as a modulation signal and a sine wave with frequency of 15kHz
and amplitude of 2Vpp as a carrier wave signal. Specific steps are seen as following:
35
3) Enable Amplitude Shift Keying (ASK) Function
Press Menu
→
Mod
→
Type
→
ASK in turn to start the ASK function.