Browse Definitions :
Definition

oscilloscope

What is oscilloscope?

An oscilloscope is a laboratory instrument commonly used to display and analyze the waveform of electronic signals. In effect, the device draws a graph of the instantaneous signal voltage as a function of time.

A typical oscilloscope can display alternating current (AC) or pulsating direct current (DC) waveforms having a frequency as low as approximately 1 hertz (Hz) or as high as several megahertz (MHz). High-end oscilloscopes can display signals having frequencies up to several hundred gigahertz (Ghz). The display is broken up into so-called horizontal divisions (hor div) and vertical divisions (vert div). Time is displayed from left to right on the horizontal scale. Instantaneous voltage appears on the vertical scale, with positive values going upward and negative values going downward.

The oldest form of oscilloscope, still used in some labs today, is known as the cathode-ray oscilloscope. It produces an image by causing a focused electron beam to travel, or sweep, in patterns across the face of a cathode ray tube (CRT). More modern oscilloscopes electronically replicate the action of the CRT using a liquid crystal display (liquid crystal display) similar to those found on notebook computers. The most sophisticated oscilloscopes employ computers to process and display waveforms. These computers can use any type of display, including CRT, LCD, and gas plasma.

In any oscilloscope, the horizontal sweep is measured in seconds per division (s/div), milliseconds per division (ms/div), microseconds per division (s/div), or nanoseconds per division (ns/div). The vertical deflection is measured in volts per division (V/div), millivolts per division (mV/div), or microvolts per division (?V/div). Virtually all oscilloscopes have adjustable horizontal sweep and vertical deflection settings.

oscillos.gif (4843 bytes)

The illustration shows two common waveforms as they might appear when displayed on an oscilloscope screen. The signal on the top is a sine wave; the signal on the bottom is a ramp wave. It is apparent from this display that both signals have the same, or nearly the same, frequency. They also have approximately the same peak-to-peak amplitude. Suppose the horizontal sweep rate in this instance is 1 µs/div. Then these waves both complete a full cycle every 2 µs, so their frequencies are both approximately 0.5 MHz or 500 kilohertz (kHz). If the vertical deflection is set for, say, 0.5 mV/div, then these waves both have peak-to-peak amplitudes of approximately 2 mV.

These days, typical high-end oscilloscopes are digital devices. They connect to personal computers and use their displays. Although these machines no longer employ scanning electron beams to generate images of waveforms in the manner of the old cathode-ray "scope," the basic principle is the same. Software controls the sweep rate, vertical deflection, and a host of other features which can include:

  • Storage of waveforms for future reference and comparison
  • Display of several waveforms simultaneously
  • Spectral analysis
  • Portability
  • Battery power option
  • Usability with all popular operating platforms
  • Zoom-in and zoom-out
  • Multi-color displays
This was last updated in December 2021
Networking
  • subnet (subnetwork)

    A subnet, or subnetwork, is a segmented piece of a larger network. More specifically, subnets are a logical partition of an IP ...

  • secure access service edge (SASE)

    Secure access service edge (SASE), pronounced sassy, is a cloud architecture model that bundles together network and cloud-native...

  • Transmission Control Protocol (TCP)

    Transmission Control Protocol (TCP) is a standard protocol on the internet that ensures the reliable transmission of data between...

Security
  • personally identifiable information (PII)

    Personally identifiable information (PII) is any data that could potentially identify a specific individual.

  • zero-day vulnerability

    A zero-day vulnerability is a security loophole in software, hardware or firmware that threat actors exploit before the vendors ...

  • DNS attack

    A DNS attack is an exploit in which an attacker takes advantage of vulnerabilities in the domain name system.

CIO
  • data collection

    Data collection is the process of gathering data for use in business decision-making, strategic planning, research and other ...

  • chief trust officer

    A chief trust officer (CTrO) in the IT industry is an executive job title given to the person responsible for building confidence...

  • green IT (green information technology)

    Green IT (green information technology) is the practice of creating and using environmentally sustainable computing resources.

HRSoftware
  • diversity, equity and inclusion (DEI)

    Diversity, equity and inclusion is a term used to describe policies and programs that promote the representation and ...

  • ADP Mobile Solutions

    ADP Mobile Solutions is a self-service mobile app that enables employees to access work records such as pay, schedules, timecards...

  • director of employee engagement

    Director of employee engagement is one of the job titles for a human resources (HR) manager who is responsible for an ...

Customer Experience
  • digital marketing

    Digital marketing is the promotion and marketing of goods and services to consumers through digital channels and electronic ...

  • contact center schedule adherence

    Contact center schedule adherence is a standard metric used in business contact centers to determine whether contact center ...

  • customer retention

    Customer retention is a metric that measures customer loyalty, or an organization's ability to retain customers over time.

Close