Oscilloscope

Overview

Moku:Lab’s Oscilloscope features two 500 MS/s analog input channels with 200 MHz analog bandwidth, 10 Vpp input voltage range, and user-configurable AC / DC coupling and 50 Ω / 1 MΩ impedance. The Oscilloscope also features two integrated waveform generators capable of producing sine waves at up to 250 MHz and square, sawtooth and triangle waves at up to 100 MHz, enabling it to simulate a system and measure it’s response simultaneously.

FAQ


Can I set the channel offset in screen divisions while zooming?

To zoom in and out while keeping the channel offset fixed on the screen, simply pan up or down with two fingers held together. This ‘rapid zooming’ technique works horizontally and on other instruments as well!


What is the difference between ‘Normal’ and ‘Precision’ acquisition modes?

Moku:Lab records samples from the analog inputs at a rate of 500 MS/s. When looking at long time spans, the data’s sample rate is reduced to display the trace on the screen. In “Normal” acquisition mode, the input is simply downsampled; that is, only every Mth sample is taken. This can cause aliasing of high-frequency signals: for example, a high-frequency sine wave may appear as a lower frequency sine wave when the oscilloscope timebase is zoomed out. In “Precision” mode, the input is lowpass filtered (averaged) before downsampling. This reduces aliasing artifacts and increases the resolution of the trace. Note that in this mode, high-frequency signals can be filtered out, so the oscilloscope trace may appear to be zero even if a high-frequency signal is present at the input.


What is timebase setting ‘roll’?

The ‘roll’ setting on the timebase control panel is especially useful for slowing changing signals, typically with a timebase of greater than approximately 100ms/div. Rather than responding to trigger events, the oscilloscope will provide a continuously scrolling signal display with the effective trigger point set at the far right of the trace display.


What measurements can the Oscilloscope make?

The oscilloscope is capable of making a wide range of measurements on both input channels and also the math channel. Tap the tape measure icon to add a measurement; tap and hold a measurement to configure. Measurements include : Frequency, Period, Duty Cycle, Pulse Width, Negative Width, Mean, RMS, Cycle Mean, Cycle RMS, Standard Deviation, Peak to Peak, Amplitude, Maximum, Minimum, High Level, Low Level, Rise Time, Fall Time, Rise Rate, Fall Rate, Overshoot, Undershoot.


What are the definitions of the Oscilloscope measurements?

Frequency
Frequency of the signal as determined by the time between rising or falling edges

Period
Time between pairs of rising or falling edges

Duty Cycle?
Ratio of the time spent above the median to that spent below it

Pulse Width?
Time the signal spends above the median

Negative Width?
Time the signal spends below the median

Mean?
Average value of the signal

RMS?
Root-Mean-Square value of the signal

Cycle Mean?
Average value of the signal, discounting partial cycles at the beginning and end of the frame

Cycle RMS?
Root-Mean-Square value of the signal, discounting partial cycles at the beginning and edge of the frame

Standard Deviation?
Mathematical description of the spread of the points in the signal

Peak to Peak?
Difference between the highest and lowest voltage in the signal

Amplitude?
Difference between the high- and low-level voltage, excluding over- and undershoot

Maximum??
Highest voltage in the signal

Minimum?
Lowest voltage in the signal

High Level?
Highest voltage in the signal, excluding overshoot

Low Level?
Lowest voltage in the signal, excluding undershoot

Rise Time?
Time taken for the signal to transition from 10% to 90% of the way from minimum to maximum

Fall Time?
Time taken for the signal to transition from 90% down to 10% from maximum to minimum

Rise Rate
Rate at which the signal transitions from 10% to 90% of the way from minimum to maximum

Fall Rate??
Rate at which the signal transitions from 90% to 10% of the way from minimum to maximum

Overshoot?
Distance the signal shoots above the maximum level before settling

Undershoot?
Distance the signal shoots below minimum level before settling