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2017

Good news! We're extending the end date for the Infiniium S-Series oscilloscope promotion, "Your Scope. Your Way." to March 31, 2018. 

S-Series Oscilloscope

The S-Series oscilloscopes (500 MHz to 8 GHz) provide you with unmatched measurement accuracy with the best signal integrity and most comprehensive measurement software for signal analysis, compliance, and protocol analysis. With "Your Scope. Your Way." promotion, you can choose ANY ONE of the following value-add offers with each S-Series oscilloscope purchase – at no additional cost:

 

Offer #1:  Get the new N8888A Infiniium Protocol Decode Software Bundle for free (supports 32 protocols)

I2C

eSPI

PCIe Gen 1Ethernet 10BaseTSVIDFlexRayUSB 2.0

USB PD 

SPI

Quad eSPI

LIN

Ethernet 100BaseTXCANUFSUSB 3.1 Gen 1

USB 3.0 SuperSpeed Inter-Chip (SSIC)

RS232/UART

SASARNIC 429JTAGCAN-FDSPMI

SATA

I2S

MIPI I3CMIPI RFFEMIPI UniProMIPI LLIMIPI D-PHYMIPI CSI-3

MIPI DigRF v4

MIL-STD-1553

 

Offer #2:  Get two N2796A 2 GHz single-ended active probes for free

N2796A 2GHz single-ended active probe

 

Offer #3:  Get 400 Mpts/channel memory for free (DSOS000-400)

 

Offer details and T&C can be found here: www.keysight.com/find/yourscopeyourway. Promotion ends March 31, 2018 so hurry!

Sniffing the air

Dogs do it all the time. But there is much more in the air than just smells. There are RF signals of all kinds all around us. How do we 'sniff' these signals out of the air so that we can observe them on an oscilloscope?

Sniffing where you can’t probe

Probing electrical voltage signals in a circuit is typically achieved using an active or passive voltage probe. If you need to measure current, most engineers use a clamp-on Hall-effect current probe that converts the magnetic field around a conductor, created by the current flowing through it, into voltage. But what if you need to monitor and verify RF signals between two sealed devices (nothing to probe), such as signals transmitted from your key fob to the receiver in the car? Or perhaps Near Field Communication (NFC) signals between your mobile phone (transmitter) and a tag (receiver)? For this you can use a RF loop antenna — sometimes called “sniffers”.

 

Download the "6 Essentials for Getting the Most Out of Your Oscilloscope" eBook.

 

Although RF loop antennas are typically used for spectrum analysis measurements, they can also be used for oscilloscope measurements. Loop antennas come in various sizes and are typically tuned for specific ranges of frequencies. In this post, I’m going to show you very briefly how you can capture key fob signals using a small RF loop antenna, based on amplitude shift-keying (ASK) modulation with a carrier frequency of 434 MHz. Detailed resources are listed at the bottom of this post.

RF_loop_antenna

Figure 1. A typical RF loop antenna

 

Sniffing and decoding automotive key fob RF signals

So, which oscilloscope would you need for the application? Since the carrier frequency in this measurement application is 434 MHz, I’ve used a 1.0 GHz bandwidth Keysight InfiniiVision X-Series oscilloscope (DSOX3104T). In brief, the steps to decode RF signals from an automotive key fob with a scope includes:

  1. Connecting the loop antenna to the scope’s Channel 1 input, terminated into 50
  2. Positioning the loop antenna near the key fob while one of its buttons is pressed to capture the single-shot burst of RF-modulated data packets (channel-1, yellow trace shown in Figure 2)
  3. As decoding the RF-bursted packets requires demodulation prior to digital decoding, you’ll also need to setup the scope to digitally demodulate the signal (hardware-based within the scope, channel-2, green trace shown in Figure 2)
  4. Decoding the digitally demodulated waveform. This can be achieved with the oscilloscope’s user-definable NRZ/Manchester trigger and decode option. Figure 2 shows the Manchester-decoded bits at the bottom of the trace display
  5. Screen display of the Keysight DSOX3104T scope

Figure 2. Screen display of the Keysight DSOX3104T oscilloscope that displays the captured single-shot burst RF-modulated signal (yellow trace), demodulated signal (green trace) and Manchester-decoded bits

 

Sniffing Near Field Communication (NFC) signals from a mobile phone

In Figure 3, I’m showing you the setup for how you can capture NFC signals generated by a mobile phone, using a larger PC trace loop antenna. Since the carrier frequency in this case is just 13.56 MHz, a 100-MHz bandwidth oscilloscope is sufficient for the measurement application.

 Capturing NFC signal from mobile phone

Figure 3. Setup to capture NFC signals from a mobile phone with a PC trace loop antenna and a 100-MHz bandwidth oscilloscope

 

Creating your own RF ‘sniffer’

What if you need a simple ‘sniffer’ that doesn’t have to be precision-tuned? Well, you can create a non-precision loop antenna yourself! Simply connect the ground clip of a standard high-impedance passive probe to the probe tip (shown in Figure 4) and – voilà – you have created an oscilloscope RF ‘sniffer’! Sure, it may not be tuned for a particular carrier frequency, meaning that the voltage levels that you measure on the oscilloscope may not be an accurate representation of the actual RF field strength. But you can still “sniff” signals out of the air to verify proper modulation and timing of your RF-modulated signals.

DIY of RF loop antenna using high-impedance passive probe

Figure 4. DIY your own RF loop antenna using a standard high-impedance passive probe

 

Detailed ‘sniffing’ resources

If you’re interested to learn in greater detail about ‘sniffing the air’ to verify modulated RF signals on an oscilloscope, here are excellent resources to get you started:

 

Decoding Automotive Key Fob Communication based on Manchester-encoded ASK Modulation – Application Note

Decoding Automotive Key Fob Communication based on Manchester-encoded ASK Modulation – YouTube Video

NFC Device Turn-on and Debug – Application Note

NFC Testing Using an Oscilloscope Part 1: Benchtop R&D Measurements

 

Written by David Liu

Routine electrical tests are time-consuming

Routine electrical tests can be mundane and quite time-consuming, especially when you’re required to repeat the same test procedure with just one or two parameter changes. Take the testing of a DC-DC converter, for example. In the diagram below, you’ll notice that setup requires a few instruments to work together, including a DC power supply, digital multimeters, a DC electronic load and an oscilloscope.

 

Typical schematic of a DC-DC converter test setup

 

Figure 1. Typical schematic of a DC-DC converter test setup

 

DC-DC converter testing

A typical DC-DC converter test procedure requires the recording of voltage, current and power values under different load conditions. The figure below simulates a table of results that you’d likely need to fill up as you complete the characterization of a DC-DC converter under test. Imagine the time that’s needed for you to manually change each instrument setting, measure the values at each test point and record them in the table. Not to mention, all those steps on repeat!

DC-DC Converter Test Table

Figure 2. Typical table for manual recording of DC-DC converter characterization results

 

Try automating routine electrical tests

The steps involved in a routine electrical test, such as the one described above, could be drastically simplified by programming the whole procedure and automating the test. But first, you need someone to write the program, and for efficiency, the program should cover steps from configuring instruments, to measuring outputs or inputs, and tabulating results.

 

 

BenchVue Test Flow saves on manual programming and testing

So, you could write your own program from scratch, or you could try Keysight BenchVue. With Keysight BenchVue, you don’t have to be a programming wizard. BenchVue’s drag-and-drop interface and its Test Flow feature lets you create simple test procedures or sequences – quickly and easily. Something that could take days with writing traditional programming languages from scratch.

 

With BenchVue Test Flow, you can:

  • Create custom test sequences easily and quickly
  • Combine multiple instruments into a sequence seamlessly for a more complete DUT characterization
  • Drag-and-drop controls for rapid test prototyping
  • Code flexibly with the capability to:
    • Incorporate various utility blocks that simplify programming including statistics, math function, step controls and loops
    • Run SCPI commands, integrated Command Expert sequence blocks, or external programs

BenchVue Test Flow intuitive interface

Figure 3. BenchVue Test Flow’s intuitive interface

 

BenchVue supports multiple Keysight instruments

Figure 4. BenchVue’s seamless support for multiple Keysight instruments

 

Using Keysight BenchVue Test Flow, you can complete the DC-DC converter test above within 10 seconds. Not only will you be able to export test results in a perfectly-filled spreadsheet, you will also be able to capture waveform files automatically.

 

BenchVue Test Flow completes DC-DC converter test in 10 s

Figure 5. BenchVue Test Flow completes DC-DC converter test in 10 seconds and exports tabulated results in a spreadsheet for easy analysis

 

BenchVue Test Flow  eases data recording, export and analysis

BenchVue Test Flow incorporates features that are designed to speed up your data analysis, so you can focus on your next measurement tasks.

  • The “preview tool” helps you validate the sequence setup at a quick glance.
  • Customize how and what measurements you’d like to view on the X- and Y-axis
  • View data logs easily in tabular form
  • For reporting purposes, or for further analysis, export data easily to popular software applications including MATLAB, Microsoft Word and Microsoft Excel

BenchVue Test Flow features for quick data analysis

Figure 6. BenchVue Test Flow’s easy setup validation with the preview tool, customizable X-Y chart and exportability to popular software applications

 

If you are looking for a software app that can easily control your instruments and simplify automation, we recommend that you check out the latest updates and features on the Keysight BenchVue page.

mike1305

Keysight Crossword Fun!

Posted by mike1305 Employee Dec 6, 2017

Hey readers!

 

For today’s blog we decided to do something a bit different. I’m a big fan of the New York Times crossword puzzle (Monday record time 4m35s, let me know yours below) and thought this would be a fun way to share that with all of you. Grab a cup of coffee and give this puzzle a try! Let us know in the comments if you’d like to see more of these in the future, or if you need any extra hints to solve it.

 

Cheers!

-Mike

 

*Download the attachment and print for the best experience*