How to Choose an Oscilloscope

picture of a group of oscilloscopes

What Is An Oscilloscope Used For

Oscilloscopes are used to analyze electrical signals in order to help debug circuits. They are used by hobbyists and amateurs alike and depending on their respective requirements, can range in price from a few hundred dollars to tens of thousands of dollars.

It’s therefore important to understand to understand how oscilloscopes, or o-scopes, work in order to understand which features you actually need. This will help determine how much you will have to spend.

For example, bandwidth is a deciding factor for many people. An oscilloscope with a bandwidth of a 100 Mhz may cost a few hundred dollars but one with a bandwidth of 1Ghz+ could cost nearly $50,000. Most non-professionals will be fine with an entry level oscilloscope in the $300 – $500 range.

On the other hand, a product developer, researcher or technician may actually need to invest in one of these high end oscilloscopes to simultaneously display mixed signals – analog activity from power supplies as well as digital circuit behavior.

So if you’re ready to step up from a multimeter and learn more about oscilloscopes, read on.

Analog vs Digital Oscilloscopes

It’s the 21st century. Nowadays almost all oscilloscopes are digital. They’re a lot more user friendly and feature-rich. If you’re looking for an analog oscilloscope, then you may have edge case requirements that call for o scope technology that’s over 20 years old.

Modern oscilloscopes have similar designs insofar as there’s an LCD monitor that may or may not be connected to a computer in order to visualize the electrical signals more clearly, and use probes (an ADC) to sample the inputs.

They come with a number of built-in functions, features and math capabilities such as FFT to help with your measurement and analysis, and there are even hand-held oscilloscopes that facilitate portability for those who need to use them on the go.

bandwidth of an oscilloscope analysis

Oscilloscope Bandwidth

Bandwidth is one of the key differentiators for an oscilloscope’s price. Number of channels, input and outputs, and memory are other features people check for as well but far more important is the oscilloscope’s bandwidth because it helps determine the highest frequency signal that your scope can consistently and accurately capture.

First, determine how much bandwidth you actually need. What will you be using the oscope for? For most people, 200 MHz is enough if you’ll only be working with audio signals. If you’re working with high frequency RF, then you’ll definitely need more bandwidth, and you’re probably a highly trained professional who doesn’t need to read this article J

Oscilloscope Brands

The oscilloscope industry is basically divided up into a B2B (business to business) and B2C (business to consumer) market, and the price points of the oscilloscopes that cater to each market reflect the target audience’s budget.

Tektronix and Keysight are the two manufacturers/brands that cater to the business/professional market. They develop the really high end oscilloscopes that costs tens of thousands of dollars. And honestly, they’re well worth it.

There are also manufacturers like Hantek, Rigol and Siglent that make more affordable oscilloscopes. They obviously have lower bandwidth and not as many features, but understandably so because they are targeted to a consumer market that spends far less due to their lower technical requirements for an oscilloscope.

handheld-oscilloscope

Hand held vs Bench Oscilloscopes

Many users need the ability to use their oscilloscope on the go as they may need to move around in several industrial or even automotive settings where access to AC power may not always be available. In this case, a hand-held oscilloscope may be needed to make floating and/or differential measurements.

Unlike a bench oscilloscope that draws its power from AC, a hand-held scope is battery-powered and usually more protected so it’s less prone to damage due to bumps and accidental drops.

Moreover, a hand-held oscilloscope has analog inputs that are fully isolated so they are less likely to be exposed to short circuits as they are isolated from each other as well as the premises’ grounded conductor.

To be fair, hand-held oscilloscopes are usually not as powerful as bench scopes, in terms of overall features and capabilities, but again, they are useful for field applications.

USB Oscilloscopes

If you’re looking for a cheap…er…inexpensive oscilloscope, then you may want to consider an USB oscilloscope. USB oscilloscopes use your computer’s screen for processing and visualization, saving the manufacturer the cost of having it built-in to the oscilloscope itself.

The may also have low capacity signal generators and power supplies and may not be as feature-rich, but they get the job done for most amateurs. There are several USB oscilloscopes available from makers such as Hantek and Diligent.

DS1054Z-Kit4-parts

Options for Purchasing an Oscilloscope

Affordable Oscilloscopes

Two popular oscilloscopes at affordable price points are the Rigol 1000 series and the low end Siglent oscilloscopes.

The Rigol 1054Z, for example, comes in two models, one with a bandwidth of 50 Mhz and another with a bandwidth100 Mhz. Note, they’re hackable so that their respective bandwidths can be easily doubled.

There is as also the Siglent 1202XE oscilloscope. It costs slightly more but it has a few more features. Both costs less than $500 and is are affordable entry-level options for many users,

Used Oscilloscopes

Another option of course is to purchase a used oscilloscope. There are plenty of good options on eBay. Be sure to check the seller’s reputation and read the descriptions carefully because, as with anything used, you could either find a great deal or have to deal with re-calibrating the scope or a device that is considerably worn down and prone to failure.

Oscilloscopes from Authorized Dealers

If you’re in the market for a high end oscilloscope, or are a business professional, your company is most likely dealing with highly trained professional sales people that offer oscilloscopes costing tens or even hundreds of thousands of dollars. You’re probably not reading this blog J

Oscilloscopes on Amazon

We recommend buying an oscilloscope off Amazon because, many times, they offer the best prices, and you get the added benefit of user reviews on many of the scopes. We’ve reviewed some affordable entry level oscilloscopes here that you may want to check out.

In addition to editorial reviews, community reviews help add additional color and perspectives – the wisdom of the crowd as they say.

Finally, dealing with a big company means you get the peace of mind of knowing that your purchase is protected and, worst case scenario, you can return the equipment at no additional cost.

How to Use an Oscilloscope

This video does an excellent job of explaining both the history of oscilloscopes as well as its basic functionality. Enjoy

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