How does the 'Load'/'Term' affect the Waveform Generator?
Written by Paul Cracknell
Updated at March 27th, 2025
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Moku:Go
Moku:Go General Moku:Go Arbitrary Waveform Generator Moku:Go Data Logger Moku:Go Digital Filter Box Moku:Go FIR Filter Builder Moku:Go Frequency Response Analyzer Moku:Go Logic Analyzer & Pattern Generator Moku:Go Oscilloscope & Voltmeter Moku:Go PID Controller Moku:Go Spectrum Analyzer Moku:Go Waveform Generator Moku:Go Power Supplies Moku:Go Lock-in Amplifier Moku:Go Time & Frequency Analyzer Moku:Go Laser Lock Box Moku:Go Phasemeter
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Moku:Lab
Moku:Lab General Moku:Lab Arbitrary Waveform Generator Moku:Lab Data Logger Moku:Lab Digital Filter Box Moku:Lab FIR Filter Builder Moku:Lab Frequency Response Analyzer Moku:Lab Laser Lock Box Moku:Lab Lock-in Amplifier Moku:Lab Oscilloscope Moku:Lab Phasemeter Moku:Lab PID Controller Moku:Lab Spectrum Analyzer Moku:Lab Time & Frequency Analyzer Moku:Lab Waveform Generator Moku:Lab Logic Analyzer/Pattern Generator
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Moku:Pro
Moku:Pro General Moku:Pro Arbitrary Waveform Generator Moku:Pro Data Logger Moku:Pro Frequency Response Analyzer Moku:Pro Oscilloscope Moku:Pro PID Controller Moku:Pro Spectrum Analyzer Moku:Pro Waveform Generator Moku:Pro Lock-in Amplifier Moku:Pro Laser Lock Box Moku:Pro Digital Filter Box Moku:Pro FIR Filter Builder Moku:Pro Phasemeter Moku:Pro Multi-instrument Mode Moku:Pro Logic Analyzer/Pattern Generator Moku:Pro Time & Frequency Analyzer
- Python API
- MATLAB API
- Arbitrary Waveform Generator
- Data Logger
- Digital Filter Box
- FIR Filter Builder
- Frequency Response Analyzer
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- Lock-in Amplifier
- Oscilloscope
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- PID Controller
- Spectrum Analyzer
- Time & Frequency Analyzer
- Waveform Generator
- Logic Analyzer & Pattern Generator
- Multi Instrument Mode
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- LabVIEW
Moku:Lab and Moku:Pro Waveform Generators have fixed 50 Ω load resistors. When you connect the output to a 50 Ω device, the output voltage distributes to the internal load and external load equally. When you connect the output to a high-z device, most of the voltage distributes to the external load.
Changing the 'Load'/'Term' on the user interface does not affect the actual driving voltage. Instead, it only changes the scale for the display. The displayed voltage under the high load is twice the displayed number under the 50 Ω load.
In the plot below, it can be seen that the 'Term' is set to 50 Ω, resulting in a voltage output of 1 Vpp.
When the 'Term' is changed to `Hi-Z`, the voltage reading changes to 2 Vpp. Although the voltage output source remains unchanged, the voltage reading in the interface is doubled because the voltage distribution on the load doubles when the load changes from 50 Ω to high impedance.
The Moku:Go has a fixed 200Ω load resistor and there is no option to change the termination.