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Test & Measurement

The Test & Measurement Blog is the place for conversation and discussion about materials and product testing, bench testing, inspection, and test equipment & strategies. Here, you'll find everything from application ideas, to news and industry trends, to hot topics and cutting edge innovations.

Complete Isolation and Extreme Common Mode Rejection are Within Reach

Posted January 11, 2017 3:05 PM by SavvyExacta

VGS measurements on semiconductors are only possible with a measurement system that combines high common mode rejection ratio, high common mode voltage and sufficient bandwidth.

Using the new IsoVu isolated measurement system you can now take accurate high-side VGS measurements. Learn how this technology can keep up with your stringent design requirements, letting you see the unseen. Download a whitepaper today to learn how to measure VGS on wide band-gap semiconductors.

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Counterfeiters Can Produce Undetectable Fake U.S. Money

Posted August 31, 2016 8:55 AM by HUSH

Cash is an interesting byproduct of contemporary economies. The assorted rectangles of ink and paper have wildly different values despite themselves being objectively worthless materials. Instead the numbers on the bills represent buying power.

The U.S. dollar, which became the world’s reserve currency in 1947, was formerly backed up by a gold reserve. This practice was eliminated in the 1970s, as global recession meant international countries began exchanging their cash for gold, which reduced the influence of U.S. currency. Instead, the U.S. made a deal with Saudi Arabia and subsequently OPEC for all oil transactions to use U.S. money. This created a foreign demand for U.S. dollars, and this remains how U.S. currency retains international value today.

Yet over the past 20-plus years, highly-advanced manufacturing and counterfeiting have also undermined the value of U.S. $50 and $100 bills, and remain a threat going forward. These notes are dubbed “supernotes,” as they of such high quality that they appear more authoritative than genuine bills.

The supernotes are made of the same hard-to-produce material, a hybrid 75% cotton, 25% linen fiber paper blend. The notes are also printed by intaglio printing, where the metal plates have lines engraved or etched, which are filled with ink, and then are compressed to the paper. Intaglio printing also gives U.S. notes their rough texture as the inks dry just slightly above the surface of the paper. Most counterfeiting operations use cheaper, less effort-intensive printing techniques, such as inkjet, offset or laser printing, that cannot replicate the intaglio texture.

These supernotes are also engineered to include security features. This includes the exclusive security microfibers found in current U.S. bills, as well as correct watermarks, security strips, and microprint lettering incorporated into real U.S. bills. Even the optically variable inks (OVIs), which cause bills to look green in one light or bronze or black in another, have been emulated. Typically, advanced OVIs and intaglio presses are only available to government agencies for document production.

Of course, there are some very minute differences. The printed quality of supernotes sometimes actually exceeds that of a real note. For example, the hands on the clock tower of Independence Hall are actually sharper and more clear on a supernote, a lamp on the street nearby is better defined, and on the front of a supernote, the letter N in the word ‘United’ has a small font misprint.

Nonetheless, supernotes are practically impossible to identify without instruments. Supernotes are confirmed by the U.S. Secret Service with mass spectroscopy, near-infrared analysis and microscopic inspection.

Evidence suggests that North Korea was likely responsible for the printing and distribution of the notes, possibly beginning back in the 1970s. Motivations were hopes of undermining the U.S. economy, while also paying for goods and products with the fake money. North Korea has a well-known counterfeiting industry that includes narcotic and prescription drugs, cigarettes and designer brands.

Another U.S. $100 bill redesign in 2013 has vastly slowed the discovery of supernotes. This Vice article suggests that North Korea has either abandoned printing counterfeit U.S. notes (in favor of Chinese notes, it seems) or they are now so good at it that fakes can’t be detected.

Turns out, money is only as good as its manufacturing.

22 comments; last comment on 09/05/2016
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Edison's Light Bulb Lives On

Posted April 11, 2016 12:00 AM by Engineering360 eNewsletter

To reduce energy consumption, and despite the chagrin of many consumers, countries around the world have severely limited or outright banned the manufacture and sale of conventional incandescent light bulbs because most of their energy consumption converts into heat, rather than light. The most common alternatives - compact fluorescents (CFLs) that contain mercury and can't dim, and still-expensive LEDs that have yet to achieve a satisfyingly natural incandescent color - have encountered considerable resistance. New discoveries suggest that perhaps the efforts to eliminate the technology will prove premature. These researchers at MIT have found a technique that will harvest much of the infrared light(heat) and convert it to visible light at higher efficiencies than CFLs or LEDs. Stay tuned.


Editor's Note: This news brief was brought to you by the Quality, Test & Measurement eNewsletter. Subscribe today to have content like this delivered to your inbox.

9 comments; last comment on 09/06/2016
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What's a Hygrometer?

Posted March 25, 2016 12:00 AM by SavvyExacta
Pathfinder Tags: humidity measurement hygrometer

The right humidity level can make or break manufacturing, testing, and other industrial processes. But what is humidity, and how is it monitored? And who needs to worry about it?

You probably know that humidity is the presence of water vapor in air or other gases, expressed as relative humidity or absolute humidity. Dew point temperature is the actual amount of water vapor in the air. Hygrometry is the study of humidity measurement, and it's important across a number of industries and applications.

Most hygrometers (humidity measurement devices) can only measure within a certain humidity range, so multiple devices may be required if a broad measurement range is anticipated.

Some applications of hygrometers:

  • Serve as reference standards for calibration and metrology labs
  • Measure the dew point in facilities where air conditioning equipment is developed and tested
  • Measure the relative humidity in environmental chambers where products like car batteries are subjected to wide temperature and humidity ranges
  • Monitor the humidity in clean rooms
  • Monitor and control the humidity in the air of moisture-sensitive pharmaceutical production processes
  • Measurement during automotive emissions testing
  • Measure dew points in air used in glass furnaces in steel mills

Do you need to measure or calculate humidity and/or dew point in your work? What devices do you use, and why?


Chilled mirror optical hygrometers are one method of measuring humidity. Want a detailed explanation of how that works, plus tips for maintenance? View Kahn's one-hour webinar!

Webinar Details:

Available on-demand until June 12, 2016.

Learn More & View Today

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Painless Vibration Testing

Posted December 28, 2015 12:00 AM by Engineering360 eNewsletter

In many mechanical systems, excess vibration indicates some kind of malfunction or potential malfunction. This new vibration tester provides instant information about machine operation based on a vast database of related equipment. It assesses misalignment, unbalance, and looseness faults and recommends appropriate repair actions - even without a prior measurement history. Test results are archived to track equipment deterioration over time. The vendor claims simple set-up and ease-of-use with no training required.


Editor's Note: This news brief was brought to you by the Quality, Test & Measurement eNewsletter. Subscribe today to have content like this delivered to your inbox.

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