Oscilloscope Basics Revisited

An Oscilloscope? What is it? For a basic starting point, it shows the heartbeat of electronic devices. Oscilloscopes give insights into electronic devices and whether or not they are operating correctly, providing a user the ability to check signal health.

The signals of devices could be voltage or current. And the goal is to make sure those voltages or currents are oscillating at the right pace or frequency. We all know electronic signal glitches are bad, and an oscilloscope can help us find them. Being able to view the signals of an electronic devices allows a user to validate it is operating as expected. If a device is not operating properly, an oscilloscope can help diagnose the problem and correct it. Most electrical engineers, either need or already use an oscilloscope. This also applies to test engineers, students, or users who work in manufacturing, repair, research, or development.

The Basics of Oscilloscopes

In its most elementary understanding, an oscilloscope displays voltage versus time, with voltage on the vertical axis and time on the horizontal axis. This allows a user to review that a device’s signal is as expected, both in magnitude and frequency. A feature oscilloscopes provide is a visual representation of the signal, so a user can view any anomalies or distortion which may be occurring. But before a user can just jump in and test, there are some things to consider.

Just like cars, there a multitude of choices when looking for an oscilloscope. A user needs to boil it down to the right bandwidth, signal integrity, sample rate, and channel inputs. Also, an oscilloscope choice needs to be compatible with any applications and accessories that may be tested. The following is a basic list of features to consider when deciding on an oscilloscope:

Bandwidth – The range of frequencies an oscilloscope can measure accurately. Oscilloscope bandwidths can range from 20 MHz to 200 GHz.

Sample Rate – The number of reading samples an oscilloscope can take per second. The more samples per second, the more clearly and accurately defined is the display of a waveform.

Signal Integrity – In a nutshell, the oscilloscope’s accuracy of showing a waveform correctly. With a device under test, a user wants an accurate reading to save from wasting time troubleshooting for a root cause problem in a device when there isn’t actually a problem.

Channels – The number of inputs to the oscilloscope. Inputs can be analog or digital. Typically oscilloscopes have either 2 to 4 channels.

Probe Compatibility – A probe is a tool used to connect an oscilloscope to the device under test. Probe types include passive and active probes, each designed for specific uses. Oscilloscope and probes need to be compatible with specific tests.

Multiple Applications – Signal analysis, protocol decode, and compliance test software can reduce the time it takes to identify and capture errors in designs. Analysis software can help a user find and evaluate jitter, create eye diagrams, perform Fourier transforms, and even diagnose crosstalk. Protocol decoding software identifies digital packets of information, trigger on different packet occurrences, and identify possible protocol errors. No one oscilloscope is compatible with all applications.

Portability – Is a portable or bench-top unit more suited for a user’s applications? Both options work the same, but if a user needs to move an oscilloscope around to many locations or from bench to bench in a lab, then a portable handheld oscilloscope would be ideal.

Oscilloscopes Are Used For Multiple Applications

Basic testing usually requires an oscilloscope that has 50 to 200 MHz of bandwidth, a passive probe, and ample sample rate, signal integrity, and 2 to 4 channels.

In using a basic oscilloscope set up, a user can spot-check printed circuit boards (PCBs), power lines for noise, shorts, and I/Os (inputs and outputs) that are not functioning properly. Also different trigger modes can be used to search for runts, glitches, and timing errors. Signals and data will need to be captured to prove the quality of designs and manufacturing. A few basic oscilloscopes can even perform Bode or frequency and phase response analysis.

The multitude of uses for which an oscilloscope can be used shows it is a versatile and widely used instrument. Oscilloscopes are used by automotive technicians to diagnose electrical problems in cars. Schools at all levels take advantage of oscilloscopes to teach students about electronics. Oscilloscopes are used in many other applications: research, cell phone signals, military and aviation testing of radar communication systems, R&D departments to design and confirm new technologies, and compliance testing.

In sum, choosing an oscilloscope is not as difficult as it is made out to be – a user needs to know what applications need to be tested, and then match up an oscilloscope’s capabilities to the application.

Advertisements

Choosing the Right Diagnostic Automotive Oscilloscope for Your Auto Repair Shop

vds3104 right

Searching for Answers: Choosing Your Oscilloscope

Every shop will have different needs and uses for an oscilloscope, so it’s important to identify your facility’s specific needs from the equipment. Here are six steps to cover so your choice is the most correct one.

Step 1: What kind of vehicles are worked on? Take a look at the shop’s mix. What kind and type of vehicles are repaired the most? What makes, models and years are seen most often? “The more specific and ‘specialized’ the work that can be provided, the better off the shop will be. Choose the 10 most worked-on vehicles, and figure out the needs for those.

Step 2: Consider what isn’t worked on. Obviously, an oscilloscope should be able to help in bringing in additional business, jobs, revenue and, as is the overall goal – profitability. Will it be a tool that can help in bringing in vehicles in the area that the shop is missing out on? Are there any other shops working on a specific vehicles? If not, can the right oscilloscope help the shop take advantage of this opportunity?

Step 3: Research oscilloscopes. Here’s where shops often get off track or go the easy route. But if the proper approach is used and the correct observance of the shop’s work mix (Steps 1 and 2), then it narrows it down quite a bit. Here are six things to consider:

Coverage. What software does the tool come with? What updates? What vehicles does the software cover? Makes and model years? Because of changes in vehicle design and capabilities, how often is the software updated? It needs to be understood what each software package is capable of diagnosing.

Training/Ease of Use. Most oscilloscopes are “plug & play” aftermarket tools. Higher-end oscilloscopes often come with a steeper learning curve for first-time users. Try to get a feel for how long it will take shop technicians to master the equipment, and what training or support is offered.

Compatibility. Some oscilloscopes are Windows-based PC or laptop-based, and that often means one oscilloscope with powerful software can provide a wide range of coverage.

Technical Support. Got hotline? Some oscilloscope manufacturers provide hotlines of sorts to call for additional information or for support for difficult diagnoses. Understand how each oscilloscope is supported.

Upgrades/Updates. Oscilloscopes are constantly being upgraded and updated. Research the companies you’re considering and see what they offer in terms of upgrades. Not only for the purpose of the software but also for the oscilloscope.

Cost. An obvious point. Do you want a high-end do it all oscilloscope, then get ready to pay significantly. There’s going to be a large discrepancy in price between oscilloscope makers. This is why understanding the work mix of the shop is important to grasp the value of the tool.

Step 4: Analyze the return. There are a lot of ways to try to analyze how valuable a diagnostic oscilloscope is for a shop. One way to analyze the return is to low-ball the return and only compare the cost of the tool (including subscriptions and upgrades) to the amount of profit made on diagnostic charges. This will gave an absolute minimum that can serve to directly pay off the tool.

Step 5: Demo the tools. Be wary of any company that isn’t confident enough in its oscilloscope to let you have it for trial period. What is their return policy? If the oscilloscope doesn’t fit your needs, can you return it NQA? Using the oscilloscope on your own is important in making the right decision.

Step 6: Implement the tools. Although this step must come after you selected and purchased a tool, it will also help to confirm your decision. Don’t just simply buy diagnostic equipment and hand it off to the technician. Create processes and systems for your shop to use it correctly, Seyfer says, and make sure to market your capabilities.

Keep It Simple

Choosing an oscilloscope for the shop can be a difficult task. The most important thing to remember, is to find the best fit for your shop. Get as much information as possible. Speak with other shops, talk with vendors, ask about it in association gatherings, and on message boards—anywhere you can. There’s plenty of information out there about each tool.

In the end, try to make the process as simple as you can.

Should you have any questions, you can contact us directly by filling out the form below.

10 Reasons Why You Need A PC Oscilloscope

vds3104 right

PC Oscilloscopes (PCOs) are rapidly replacing traditional digital storage oscilloscopes (DSOs) as the essential item for your test equipment arsenal. Here are 10 reasons why:

  1. Compact and portable units
  2. Uses your PC monitor to provide a large and detailed color display
  3. Signal storage is limited only by your PC’s storage capability
  4. Captured waveforms and instrument settings can easily be shared with others
  5. New functionality through free software updates
  6. Can be used with desktop or laptop PCs
  7. High-speed USB 3.0 connection (parallel port oscilloscopes are also available)
  8. Hardware and software in one package
  9. Use your PC Oscilloscope for data acquisition
  10. A complete test and measurement lab in one unit

1.  Compact and portable units

By integrating several instruments into one small unit, PC Oscilloscopes (PCOs) are lighter and more portable than traditional test equipment. When used with a laptop computer, you can carry a complete electronics lab in the same bag as your PC.

2.  Uses your PC monitor to provide a large and detailed color display

The display of a traditional oscilloscope is limited by the physical size of the oscilloscope, and may only be a single color. With a PC Oscilloscope your computer controls the display, so not only do you get a full color display, but the display can be the size of your monitor, projector or plasma display.

3.  Signal storage is limited only by your PC’s storage capability

PC Oscilloscopes store the signals that you are measuring directly on your PC. With the power of today’s modern PCs this gives you vast storage capabilities. Along with allowing you to record lengthy signals this also lets you save signals for reviewing at a later date.

4.  Captured waveforms and instrument settings can easily be shared with others

Need to show your customer or colleague the signal you have captured? Just save the waveform and email them a copy. They don’t have a copy of the oscilloscope software? No problem – just export it as text, an image or in a binary format for use with third-party software. (If they want to set up their equipment to run the same test, simply send them the oscilloscope settings too.)

5.  New functionality through free software updates

If you’re lucky you can return a traditional DSO to the supplier for a firmware upgrade and maybe get improved functionality. With a PC-based oscilloscope new features and improved functionality can be added at any time with a simple software update. Free software updates means that a PC Oscilloscope is one of the few things that can actually become more powerful and useful with age.

6.  Can be used with desktop or laptop PCs

PC Oscilloscopes are external devices that are connected to your PC using the ubiquitous Universal Serial Bus (USB). Virtually every laptop or desktop PC sold comes with multiple USB ports so there’s no problem using your PC Oscilloscope with either a desktop or a laptop PC.

7.  High-speed USB 3.0 connection

USB 3.0 can transfer data at speeds of up to 1 GS/s. Using powerful PC Oscilloscope software it give you incredible performance with fast screen updates and the ability to stream data.

8.  Hardware and software in one package

Choose PC Oscilloscopes that come complete with the hardware and software in one package.

9.  Use your PC Oscilloscope for data acquisition

Using the sw, you can transform your PC Oscilloscope into a data logger that can log data over extended periods of time.

10.  A complete test and measurement lab in one unit

When you buy a PC-based oscilloscope make sure you don’t just get an oscilloscope: make sure you also get a spectrum analyzer, meter and data logger rolled into your PC-Oscilloscope choice. Some models even include a built–in signal generator or arbitrary waveform generator. So with a PC Oscilloscope you really do get a complete test and measurement lab in one cost–effective unit.

NorthTree Associates is a distributor and supplier of Electronic Test & Measurement Equipment. Companies represented include ITIC USB 2.0 Protocol Analyzers, LabNation SmartScopes, Micsig Oscilloscopes, Oscium iOS Test Tools, OWON Oscilloscopes.