Tag Archives: Electronic test equipment

US DOMINATES USED TEST EQUIPMENT MARKET AT 90%!

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US DOMINATES USED TEST EQUIPMENT MARKET AT 90%!


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According to Used-Line Research US DOMINATES USED TEST EQUIPMENT MARKET AT 90%! Click To Tweet

What’s behind this astronomical growth and what does it mean for the rest of the world?

As we come to the close of a successful 2015 sales year, we at Used-Line want to share some of our market observations and projections with you, our valued customers.

Used Test Equipment Market Snapshot.

A simple look at the Used-Line Dealers Directory shows North America as the most dominant of the 5 major global markets today by far, with over 70% of our dealers embedded and handling 92% of the products listed.

Used-Line Dealers Directory shows - 70% of North American dealers handling 92% of the products listed Click To Tweet

Europe, handling 6.2% of products, is a very distant second, followed by Asia, Oceania and the rest of the world.

Why is the US Market Growing?

America is experiencing a period of economic growth. The Bureau of Economic Analysis estimates the real gross domestic product (GDP) for 2015 increased at an annual rate of 2.1 percent in 2015 Q3. Employment was up, as well as personal income (up 0.9%) and market optimism translated into higher buying power.

A $4.13 Billion Growth Market

MarketsandMarkets consulting predicts the automated test equipment market will reach $4.13 Billion by 2020, fueled by an increased demand for consumer electronics, more complex designs and a growing need for more effective testing.

But even with the US occupying such a big chunk of the market, other regions are still dealing with a potential market of close to half a billion dollars.

MarketsandMarkets predicts the automated test equipment market will reach $4.13 Billion by 2020 Click To Tweet

But what does the future look like for these smaller markets?

Growth Potential for Other Regions

Despite their relatively small share of the used test equipment market, smaller markets have also grown.

used test equipment market
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The Asia used test equipment market, which only had 7% dealer representation a few years ago, now has 14.7%.

The Asia used test equipment, which only had 7% dealer representation a few years ago, now has 14.7%. Click To Tweet

Wireless network expansion in Asia and future developments on the planning boards mean future market growth opportunities. Plus the implications of the recent Climate Change conference in Paris mean a whole new restructuring of global industry of which Asia and other small markets will be scrambling to take advantage.

In other words, the market could grow even more than analysts estimate.

Used-Line will be keeping a close eye on this and other trends in Used Lab, Test, Measurement and Semi Equipment Market and let you know what we see in future updates.

We at Used-line will continue to do everything we can to connect you to the used test equipment market bringing you the latest news, market reviews and analytics to help you take advantage of the market.

Established 16 years ago, Used-Line has grown to become an acknowledged leader in the field of Used Lab, Test, Measurement and Semi Equipment with over 775 used equipment dealers worldwide, over 300,000 trusted used equipment listings and hundreds of thousands of customers,.

Used-Line connects thousands of new buyers and sellers of quality used and new high-tech and scientific equipment every month.

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Handheld Spectrum Analyzer Competes with Benchtops

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Frequency coverage from the Anritsu MS2720T gets as good as 9 kHz to 43 GHz in model MS2720T-0743, the high end of this series of spectrum analyzers, which starts at its lower end (in terms of frequency) with a model that boasts a continuous frequency range of 9 kHz to 9 GHz. Not too shabby. Launched in December, 2012, this almost two-years-on-the-market handheld could well compete with today’s benchtop analyzers (without external mixers) in the frequency specification department.

Let’s take a look at just a few of the other specs associated with this instrument:

  • Resolution Bandwidth from 1 Hz to 10 MHz
  • Sweep mode speeds: Allow a resolution bandwidth of 30 kHz to 10 MHz with almost no impact on sweep speed
  • Dynamic range is >106 dB in 1 Hz bandwidth at 2.4 GHz
  • DANL is -160 dBm in 1 Hz bandwidth at 1 GHz (preamp on)
  • Phase noise is -104 dBc/Hz at 10 kHz offset at 1 GHz
  • Option of tracking generators from 100 kHz to 20 GHz (full-band)

Read more in the Used-Line T&M Specs pages as well as in the Related Articles below. Do check out the many capabilities available as options for the MS2720T. Not only all the signal analysis packages that a wireless engineer may need for the various data rates of carriers, but a vast selection of analyzers, such as power meter, channel scanner, GPS Receiver, and Interference Analyzer are available as options.

Used Anritsu MS2720T | used-line.comThe Spectrum Master™ MS2720T series provides field technicians and engineers with performance that rivals a benchtop spectrum analyzer. The MS2720T features a touchscreen, full-band tracking generators to 20 GHz, and best-in-class performance for dynamic range, DANL, phase noise, and sweep speed, providing unprecedented levels of spectrum monitoring, hidden signal detection, RF/microwave measurements, and testing of microwave backhauls and cellular signals.

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Anritsu suggests that this spectrum analyzer, at 8 pounds “fully loaded” is light enough to take up a tower. Well, you’re not going to get me up any tower, thank you very much, with or without a handheld spectrum analyzer.

CN Tower, Toronto, Canada

CN Tower, Toronto, Canada (Photo credit: P.Naumann)

I do have quite a bit of trouble picturing an RF engineer making his way up the CN Tower, for example, with a benchtop instrument, so there must be some brave engineers who scale the heights – with their handhelds!

If it was I who had the responsibility of handling this instrument, I would be very much inclined to avail myself of the Anritsu Remote Access Tool, which lets the user sit in the comfort of his lab or office while controlling the spectrum analyzer over a LAN connection, and analyze data with the Anritsu Master Software Tools – in-between his sips of coffee.

But then some folks are made for reaching for the sky, and others are not.

Anritsu webpage for Spectrum Master MS2720T

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Chickens and the Unbroken Chain of Calibration

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A recent discussion in the LinkedIn group, Metrology & Test Measurement, on the “unbroken chain of calibration” has driven me to hone in on my personal understanding of measurement uncertainty. I am ashamed to say that I know virtually nothing (0 ±0.0031415929) about calibration despite having worked as an electronics technician in the ’90’s. My excuse is that ISO 9xxx only hit the repair floor in the ’90’s. (Well, that’s why it was called ISO 9000.)  But the National Bureau of Standards (NBS), which predates the National Institute of Standards and Technology (N.I.S.T.) by 87 years, has been around since 1901.

logo of National Institute of Standards and Te...

Logo of National Institute of Standards and Technology (Photo credit: Wikipedia)

And the NBS was predated by the International Bureau of Weight and Measures (BIPM in French). In any case, I’m not quite sure how to connect ISO 9xxx with calibration. It must come into it somewhere. All I remember was what kind of shoes to wear and grounding rules. I guess you could say that my uncertainty around these topics is not measurable or traceable!

How do we arrive at an unbroken chain when it comes to metrology? Let’s go to the start of the chain. We will use N.I.S.T. for discussion purposes but really it applies to any of the international organizations that set standards for metrology.

  1. We start with a reference point. This is a universally known measurement value of a particular measurable event. For example, the melting point of ice. (N.I.S.T uses a thermometer as an example on their website.)
  2. This reference is used as a standard by N.I.S.T. I assume that means that a correctly calibrated thermometer will measure – well, I’m not sure exactly what it will measure. It is close to 0 degrees Centigrade. There are various factors that can determine the temperature, such as atmospheric pressure and the purity of the actual water that the ice is composed of. The point is – a standard is set that will be used to begin the chain. This standard is the reference that all other measurements down the chain are going to be traced back to.
  3. Going down the chain, we compare the measurements of the next instrument to be checked against the N.I.S.T. measurement , then document the differences in the results. Depending on the conditions of the measurement, we can make the necessary adjustments needed to arrive at the most accurate measurement but can never be absolutely certain of a true value. Like much of life, we do our best. The “best” is a range of values that approximates the value of the N.I.S.T standard. This range of values is the range of uncertainty. You know that somewhere in this range, lies the true value and if you calibrate an instrument to show results within this range, you should be able to certify your instrument as calibrated according to the standard. If along the way, you lose the reference, your instrument cannot be considered to be calibrated according to the N.I.S.T. standard.

I know! This is a rather crude, simplistic explanation of the process. I “did my best”!

I got further confused after my visit to the supermarket today. They had fresh whole chickens on sale with a limit of 6 Kg per customer. For the customer’s convenience, a scale was placed near the chickens, allowing the customer to verify the total weight of his selection. The trick was to see whether you could get four chickens for 6 Kg, despite the average weight of 1.55 Kg per chicken. You do the math now. It seemed a shame to buy only three chickens and thus not take full advantage of this special sale. Four chickens were over 6 Kg and three were under by quite a bit.

Chicken

Photo credit: P. Naumann

Well, I came pretty close. I managed to find two smaller looking birds and my total weight on the scale (when last was it calibrated, I wonder?) was 6.14 Kg. I went over to the poultry supervisor and told him that I was a little over the maximum weight allowed, and with a smile on his face, he said, “That’s fine.”

<!–Here’s the moral of my little story–>: The more accurate our measurements are, the more honest we can be in our relationships with customers, clients, and other businesses. However, sometimes in life a little uncertainty goes a long way when it comes to give-and-take with others. <!–End of moralizing–>

Of interest:

 

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Three Ways to View Power Analyzers on Used-Line.com

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Do you know that there are at least three ways (maybe there are more) to view Power Analyzers on Used-LIne.com? Of course, the same applies to many of the other categories on Used-LIne. But today we are going to focus on just one instrument category – power analyzers – for illustrative purposes.

These three paths all serve different purposes. Used-Line has so much to offers its visitors!

1. View Power Analyzer Listings

Let’s talk about listings first because this is why a potential buyer of a power analyzer will visit Used-Line.com.

How do you find power analyzer listings on Used-LIne?
Well, I could send you the Used-Line Help manual. No. Let’s be honest. Which of our users really need help finding equipment listings on our website?

You probably fit into one of the following four user profiles:

  1. You are a frequent visitor to Used-Line and have been for years, and could probably give a class on how to navigate our website.
  2. You’ve been keeping up with our blog (you have, haven’t you?), and have learned all the tips and tricks for browsing equipment on Used-LIne.
  3. This is your first visit to the Used-Line website. You are in the market for a power analyzer and your favorite search engine brought you here.
  4. You have no interest in power analyzers or in test equipment in general. You simply enjoy reading this blog!

Profile 1: You know what you’re doing.
Profile 2: You’ve learned what to do.
Profile 3: Used-Line developers have made searching on Used-LIne such a cinch, there is no need for instruction.
Profile 4: Keep on reading!

So, no instructions needed – only a link: Used-Line Power Analyzer Ads.

Now that you’ve seen the listings, how about some descriptions of the various power analyzers that are listed?

Which takes us to Used-Line’s specifications pages for test and measurement equipment.

2. View Power Analyzer Specifications

If you followed the link to the power analyzer listings on Used-Line, you will have noted that there are 871 listings (as of today’s date)! Of course, you may have already decided which model you want, or you are a dealer looking for a specific manufacturer’s analyzer for one of your customers. But, what if you’d like to know a little more about a particular model? Or you want to check specs and features of a number of models before making your purchasing decision? What kind of power analyzer operation modes are essential to your work environment? Is harmonics measurement a must-have feature?

In other words, you would like to learn more about what types of analyzers are available and drill down into some specific characteristics about the various models in the market.

Here’s what you can do:

    1. Visit Used-Line’s T&M Specifications pages.
    2. Choose Power Analyzers.
    3. Browse the analyzers if you wish, then select one that you are interested in, for example, the discontinued Fluke 435. And here it is.
      Used Fluke 435 | used-line.comFind your used Fluke 435 Power Analyzer at used-line.com, the Online Marketplace for used Test and Measurement equipment.

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And here’s the best part! After studying the specs and features of the Fluke 435, you may decide this is just what you have been looking for. Scroll up the very page you landed on to view the Fluke 435 features description and you will find all the current Fluke 435 listings on Used-Line.

3. View the Power Analyzer Glossary

Yes, Used-Line actually provides a glossary of terms. Most, but not all the terms, are key specifications organized by instrument. Figuring that most of our users are familiar with the specs of the instruments they are interested in, we’ve hidden the glossary in the small fine print that can be found at the bottom of each page. Go ahead and see if you can find it. You just never know when you may need to look up a spec description while browsing our listings. Let our glossary get you started on your search for specification definitions. In case you don’t have a magnifying glass on hand, here’s the link. Of course, you want the Power Analyzer glossary, so that in case you were losing sleep wondering what Total Interharmonic Distortion really is, click below to find your answer.

Power Analyzer Glossary Terms | used-line.comA power analyzer, also known as an energy analyzer, is an electronic device that measures single-phase or three-phase electrical energy as it flows through a circuit or is distributed through electronic or motorized equipment. Electrical measurements commonly taken with a power analyzer include volts, amps, watts, frequency, reactive power hours, maximum power, phase angles and harmonic distortion.

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And you thought that Used-Line is just a market place for pre-owned hi-tech and scientific equipment?! Of course, it’s that! And much, much more.

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What to Consider when Purchasing a Digital Multimeter

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The Digital Multimeter (DMM) is the most fundamental test and measurement instrument in the electronic technician kit or engineer’s lab bench. It provides a number of functions, the most common being resistance, voltage and current. Secondary functions can include temperature, induced current, low frequency measurement, and other routine tests needed to troubleshoot circuits.

DMM types

Many technicians use more than one digital multimeter, as they tend to be designed to suit a particular purpose in various environments. A DMM used in a clean room or laboratory is totally unsuitable for use in an outdoor environment or under harsh or hazardous conditions. In practical use, the DMM may need to be operated while wearing gloves during an ice storm, or may need to be handheld, extremely compact, and lightweight for portability. They can be rack mounted in a semi-permanent installation to be in close proximity to equipment that needs to be constantly monitored.

Here is an example of a DMM that can operate in temperatures below -40°C: The Agilent U1273AX.

U1273AX Specifications and FeaturesLearn more about the various features and specifications for the U1273AX.

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DMM accuracy standards

Some DMMs are functional and practical, even without routine regular calibration certification. When the tolerance of a resistor may be 10% or 20%, a DMM accurate within 3% is generally sufficient. In the days of analog D’Arsonval meters, parallax distortion and the vagaries of electromechanical movement could result in erroneous readings near 2 to 3%. DMMS are far more stable and immune to misinterpretation of the readout.

 DMM longevity

DMMs have a relatively high attrition rate. This is the result of multiple meters required by each technician in the field and not so much a failure of an instrument. DMMs are designed to be used hundreds of times a day, both in laboratory and field conditions. Field equipment is often subject to abuse from impact of a dropped instrument to total immersion in water and similar environmental hazards. Laboratory equipment needs to be replaced as technologies advance and evolve.

DMM features

DMMs are basically the same instrument, regardless of the make or model. What distinguishes one from another are cosmetic appearance and the user interactive interfaces. Each of these differences are highlighted as features. Not every meter can have every feature; it is up to the technician to know which configuration on a DMM is optimal for any given situation.

DMM advanced or enhanced features

Some typical enhancements include dual displays, RS-232, USB or IEEE computer interfaces, audible alarms or tone feedback, which enables the technician to keep his eyes on the device under test rather than on the meter. High-priced options include very tight measurement tolerances. Some enhancements can include backlit LCD displays, as opposed to LED displays. Induced current “clamp meters” and similar exterior measurement accessories are usually optional, but may be included as a part of a package. Some features include hold and store min/max readings, auto-ranging or auto-sensing circuitry and similar hands-free operation. If multiple and various readings are necessary, these features can offer a vast improvement over manual ranging and repeated button-pushing to change DMM settings.

Here is a DMM with a USB host port on the front panel: The Tektronix DMM4040.

DMM4040 Specifications and FeaturesLearn more about the various features and specifications for the DMM4040.

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 Advantages of used DMMs

Of course, this is where Used-Line comes into the story. Leasing companies, larger companies employing scores of technicians, or smaller small- to medium-sized businesses seeking to stay within tight budgets can be well-served by considering procurement of used and re-certified, discontinued models or factory-refurbished DMMs. This is a cost-effective solution that will serve the company now and into the future. All technicians have particular makes and models of test instruments that they have high-confidence with using every day. In field applications, many techs prefer Fluke and Simpson meters for their ruggedness, durability and useful features without resorting to gimmicks or unnecessary bells-and-whistles. Given that some DMMs can cost over $10,000, depending on the degree of precision and accuracy required, buying used or as-new discontinued instruments can make or break a budget.

 Selecting the right DMM

Choose the best quality instrument that meets your need. With higher-priced test equipment it is a wise idea to lease an instrument to ensure its suitability to the task. Realize that equipment turn-over for many of the top leasing companies is due to deprecating features or advancing technology. Leasing companies frequently sell their equipment to used-line.com clients in sufficient quantities to make offering them at steep discounts possible, with no sacrifice to name-brand quality, dependability and service.

We can’t exit this blog post without showing a Fluke. If you’re looking for 365-day stability, have a look at the Fluke 8508A reference multimeter.

8508A Specifications and FeaturesLearn more about the various features and specifications for the 8508A.

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On Views, ClickThroughs, and RFQs: Tracking your Listings on Used-Line

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If you’re wondering why your listings on Used-Line.com generate many VIEWS, but a very low CTR (Clickthrough Rate) with a decided lack in RFQs, then you are asking the right questions.

How do you check if your ad (listing) is getting the views but not the clickthroughs?

Used-Line now offers a Statistics service that can show you all the activity taking place on your listings – both individual and overall listings. We previously discussed how to write a good sell ad for Used-Line. Now let’s find out if you really do need to work on your ads – or if, in fact, you are doing OK.

The new Used-Line Statistics service can tell you how your listings are doing by providing you with:

  • Instant views of the effectiveness of your listings overall
  • The ability to drill down into the specific statistics of individual ads

Okay. So how do we retrieve all this important information?

To view overall Statistics of all your Used-Line listings for each month

  1. Log in to your Used-Line account.
  2. To view overall statistics of all your listings, click Statistics under My Used-Line on the left side of the page. View statistics for your total listings for each month in the following four graphs:
    • RFQs received: Indicates how many Used-Line buyers sent you a Request for Quote (RFQ) for items you advertised.

      RFQs received

      RFQs received

    • Views – product pages: Indicates how many potential buyers saw your postings.

      How many users viewed listings

      How many users viewed your postings

    • Click-throughs to site: Indicates how many Used-Line visitors visited your company website.

      Number of click-throughs to your site

      Click-throughs to your site

    • Click – view phone: Indicates how many Used-Line visitors clicked the Seller phone number button in your ads.

      Number of users that clicked your Phone button.

      Number of users that clicked the Phone button.

To view statistics for your individual listings

  1. If you have not already done so, log in to your Used-Line account.
  2. To view individual listing statistics, click My Ads under My Used-Line on the left side of the page. Each ad is in the ItemID column in the My Ads tab. You can view the specific statistics for each of your ads in the four columns to the right of the ItemId column:
    • Views: The number of potential buyers that viewed the ad since it was first posted
    • Site: The number of Used-Line visitors that visited your company website by clicking the Visit Website button in the ad
    • RFQ: The number of RFQs that have been sent for the item you described in the ad
    • Phone: The number of Used-Line visitors that have clicked the Seller phone number button in the ad

Note: At times, you may want to update a listing because of new or changed information. This is fine, as long as you realize that your listing will be reset. When a listing is reset, the statistics for that listing are reset. As a result, only the statistics for the most recent version of your ad will be shown.

So, let’s get tracking!


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Why not rent? (Part two of two)

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In the last blog, I introduced a  February 2013 Scope Junction article that delivers the results of a survey on scope rentals. Readers were asked how often they had rented an oscilloscope. Of the 152 users who responded, more than 53% answered in the negative – they had never rented a scope.

Part One of this blog discussed a couple of points to consider if you are thinking about renting or leasing equipment instead of purchasing. Affordability was weighed against cost-effectiveness and the number of variables that can impact the ultimate cost of an instrument . As well, predicting the future of the industry was considered a factor in rental decisions.

Here are a couple more considerations.

Flexibility. You can rent state-of-the-art equipment that your budget does not allow you to purchase. For specific projects with stringent high-end specification requirements, a short-term rental lets you perform specialized tasks that you normally would not be able to run without the unique instrumentation features or specifications required for them. And – without breaking the bank. Although the flexibility of this type of short-term rental is attractive, it does demand more than a comfort level with the specs in order to match those required by the project with the capabilities of the instrument you intend to rent.

Test-drive an instrument. While renting, you can gauge an instrument’s performance strengths and weaknesses in your lab. Many instrument dealerships offer both rental and leasing terms. After leasing for a particular time period, you may be offered purchasing options at reduced terms. At this point, you should be able to clearly assess the suitability of the instrument as a permanent fixture in your lab.

And now for a little bonus tidbit. Or should I call that tipbit?

How to Find Dealers that Rent Out Equipment on Used-Line.com

The Used-Line Dealer Directory lists more than 900 dealers. How do you locate those that do offer rental equipment as one of their services?

  1. On the Used-Line.com home page, click DEALER DIRECTORY in the column on the right side of the page.
  2. In the Dealer Directory, use the filter on the left side of the page to choose the type of equipment you need: T&M, Lab, or Semi.
  3. Narrow your search further by Location and by product Specialization.
  4. Open the Services list, then select Rentals to view all the companies that offer rentals in the type of equipment you need.

    DD Services with Rentals

    DD services with rentals

 


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Why not rent? (Part one of two)

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In a February 2013 Scope Junction article, Michael Dunn delivers the results of a survey on scope rentals. Readers were asked how often they had rented an oscilloscope. Of the 152 users who responded, more than 53% answered in the negative – they had never rented a scope.

I’m wondering – why not?

Well, I know that there is that warm, fuzzy feeling one gets from owning one’s own stuff. There’s also the Guiltfree Factor. If you own something, you don’t get that oh-no-it’s-not-mine reaction when you spill your morning coffee on the bezel.
But, emotional issues aside, what’s on the plus side for renting a scope – or any piece of test or laboratory equipment? Here are just a few well-known, but worth repeating, advantages of renting equipment.

Affordability. Rental can be more affordable than purchasing, particularly for short-term periods and if support and maintenance are included in the terms. However, the cost of both renting or purchasing equipment needs to be carefully calculated. There are many variables, including natural depreciation of the instrument, usage, the condition of the instrument (new, used, refurbished, calibrated), specifications, configurations, need for support and repair, and yes, even size. The cost of a portable spectrum analyzer, for example, cannot be calculated using the same formula as one would use to cost a roto-molding independent-arm machine. Every company must, of course, use its own formulae for calculating the cost-effectiveness of renting or purchasing equipment.

No need to be an industry prophet. When you purchase, you need to factor in the future. When you rent, you can, well, not ignore, but somewhat downplay the effects of depreciation, usage, repairs, growth and changes in the industry, and internal turbulence within your company. You need not spend too much time wondering how much dust your instrument may be gathering at the end of the warranty period, or whether it will still be happily chugging along. A child’s “I need it now” philosophy very much suits the rental option. A year down the line is not really significant because you can swap the unit, or simply not renew the rental contract.

Stay tuned for part two, in which I’ll talk about a couple more rental considerations, and more.


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Basic BERT

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Not that a BERT is a basic instrument by any means. But I thought (while still in a techie mode – or would that be mood?) that I would bring you a pretty basic article on quite a complex test and measurement instrument. So grab a cup of coffee, curl up in front of your screen, and enjoy!

The Bit Error Rate Tester (BERT) is the test and measurement (T&M) device of choice when checking transmission and reception quality over telecommunications lines. These lines can be copper-to-copper, twisted pairs – such as Ethernet – coaxial cable, cellular phone (as 4GLTE) or fiber optics. Typically, all of these methods are used and they are often run through radio frequency repeaters, microwave, or satellite links. The BERT is also used to troubleshoot for problem areas, check repairs to circuits, and used to test alternate or secondary (fallback) transmission paths.

The BERT’s function is to stress test transmission lines to isolate sources of noise, jitter, intermittent connections and impedance mismatching. There are several types of stress testing. These can include maximum voltage throughput, as when sending all ones (1s), minimum voltages tests as all zeros (0s), forward error correction (ECC) and error detection and correction overhead. Alternating or pseudorandom bit streams are used to simulate typical traffic over the lines. There are far too many mathematical models and engineered algorithms to list in detail, but they are critical in the selection of the equipment.

BERTs can use a variety of multiplex and modulation modes, the more common commercial systems using some form of Phase Shift Keying (PSK) and other forms of signal concatenation. The major components of a BERT include a modulator/demodulator (“modem”) to connect the BERT to the transmission lines, a pattern generator, a clock to synchronize BERTs and establish baseline timing, an error detector, often some sort of digital analyzer to visually observe or record the devices under test, and a computer interface.

The complexity of digital transmission necessitates the use of equally complex – and generally expensive – specialized test equipment. The cost can easily be doubled when end-to-end testing from both termination points is required. As a practical rule, most tests can be run using farside or nearside loopbacks, which allow a single BERT to generate the patterns and detect errors sent back to itself via the loopback.

HP/Agilent and Tektronix BERTs dominate the field in this particular technology; however, Anritsu  has a long history of manufacturing leading edge telecommunications test and measurement equipment. More than 95% of the BERTS costing $10K and up are made by these manufacturers. Features, flexibility, and suitability to a purpose have resulted in some very expensive — $100K BERT test systems. Systems designed to a single purpose, such as DS line testing, can be much more affordable. For the field technician, companies such as Fluke and GAO handheld BERTs provide techs with rugged, durable, and portable solutions. Options such as pass-through of the original traffic can be a valuable asset when making live tests or in mission-critical applications, where the transmission line cannot be taken completely out of service.

Necessity for super-high frequency (SHF) and extremely high output (EHF) and input frequencies, USB 3.0, the most recent Windows O/S, and similar hardware and software user interfaces are all desirable features that can add significant cost to a unit. What used to be considered frills and gimmicks are now required features.

HP/Agilent and Tektronix have different approaches to the same issues, yet in the end, the results are the same. Without putting too fine a point on it, Tektronix instruments are more conducive to the laboratory/engineering set, while HP/Agilent is more focused on the field/maintenance group. This is a purely subjective opinion, generally based on an individual’s tastes rather than specific features. What is far more valuable is the capabilities of whichever BERT is preferred. Does it operate at the frequencies required? Can it generate the patterns necessary for test and evaluation? Is the instrument modular or easily upgradable without factory intervention? Which BERT has the best ROI potential?

Handheld portable units are much easier to compare, since they are more likely to be designed for a specific communications protocol, as T1/DS1, E1, or OC1. Desirable features in all handhelds, regardless of protocol or interface, are durability under extreme field conditions, the ability to bridge or pass-through communication modes that are transparent to the traffic, and enough flexibility to meet any reasonable situation likely to be encountered. Often the answer is defined by the question: Would you rather drop an $8000 HP or an $800 Fluke, given that both are testing an identical circuit?

As the telecommunications network is continuously evolving, it is necessary to keep your T&M as close to the leading edge as possible. Competition is too intense and customer demands are too critical to try to short-cut on quality control and rapid response to a call for repair. Top of the line, stable, and trustworthy T&M can save many times its cost by ensuring high uptime and low mean time to repair networks and transmission lines.

Ready to compare some Berts – both new and discontinued? Check them out in Used-LIne T&M Specifications.


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Measurement of Harmonics using Spectrum Analyzers

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Occasionally I get into one of my more “techie” moods, and I feel I have to share with you an application note or white paper written by an engineer from one of the three or four big test and measurement equipment manufacturers. They really know their stuff and I think it’s worth sharing even if you don’t intend to own any of their equipment. (And maybe you do!)

In an application note (1EF78) on the measurement of harmonics, Rohde and Schwarz’ Dr. Florian Ramian discusses the theory of harmonics, problems in measuring the non-linear components of a circuit, and the advantages of the R&S®FSW signal/spectrum analyzer’s high pass filter for harmonic measurements.

R&S FSW Signal/Spectrum Analyzers

R&S FSW Series

He explains the need to isolate the harmonics generated by the measurement instrument from the harmonics of the device under test (DUT). Typically a spectrum analyzer is the measuring instrument of choice because of its ability to simultaneously display both the actual signal, and the harmonics of the signal. He describes how the high pass filters of the FSW preclude the need for further RF attenuation to the signal to reduce harmonic distortion, thus keeping the noise floor low, and increasing the sensitivity of the measurements.

That’s all I’m going to say about it. Take a look at Dr. Ramian’s discussion yourself in the Rohde & Schwarz application note (in PDF format).

If you want to take a look at the features and specs of one of the FSW’s, here’s the FSW43 on Used-Line.com.


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