Digilent Analog Discovery 2 Review | Workbench Wednesdays

element14 Presents
2019-12-18

The Analog Discovery 2 combines all the equipment found on a typical electronics workbench into one small package. It packs an oscilloscope, logic analyzer, power supplies, spectrum analyzer, and so much more. As impressive as the hardware is, the Analog Discovery 2’s software, called Waveforms, is fantastic as well. You can configure it for any measurement situation, and it has extensive scripting capability. See if you should be considering adding the Analog Discovery 2 to your electronics workbench.

My day job causes me to travel on a regular basis. Sometimes that means taking my circuits with me. I picked up an Analog Discovery 2 so that I could take test equipment with me. It’s a small enough box that fits nicely into my bag. The one significant trade-off is that it requires a PC to be functional. However, for travel, that works out great.

The key functions the Analog Discovery 2 provides are:

  • 2-Channel oscilloscope
  • 2-Channel function generator
  • Voltmeter (not DMM!)
  • 2-Channel Power Supply w/ negative voltage
  • 16 Digital Channels for Logic, Protocol, and General Purpose I/O
  • Network Analyzer (Bode Plots!)
  • Spectrum Analyzer
  • Impedance Analyzer

There are probably other functions, but that covers the major ones. Years ago, I reviewed the Virtual Bench from National Instruments. While the Virtual Bench has better specs than the Analog Discovery 2, the difference in price points is staggering. You can get the AD2 for $200-300.

Check out how some of the features work and my thoughts on this device in this Workbench Wednesdays review.

See show notes on element14

Function Generator Basics | Workbench Wednesdays

element14 Presents
2019-11-27

Generating signals with a waveform, function, or arbitrary generator lets you test all kinds of circuits. Learn how to get a function generator to output a signal, the 3 types of waveforms you can create, and which controls matter. James, the Bald Engineer, explains the difference between analog and digital generators.

The video introduction is my first attempt at doing an LGR style “Tech Tales” story. It is short with only a few images. However, it is something I would like to do more of in the future. My professional career started at Agilent right when they split off from Hewlett Packard. Most of my co-workers had been there while Bill and Dave still worked at the company. Even though the computer division took the name, Agilent was HP’s core: test and measurement.

Someday I hope to see an actual 200A. Their place in history has become legendary. Some people say that Disney’s Fantasia could not be produced without it. However, Bill (or Dave) set the record straight. Disney’s engineers could have used another piece of equipment, however, they did select the 200A.

See show notes on element14

Logic Analyzer Basics | Workbench Wednesdays

element14 Presents
2019-11-06

Logic analyzers capture digital signals and then display a waveform or list. Serial busses like I2C, SPI, or UART (Serial) can be decoded or triggered on when there are problems in your circuit. In this video, learn the basic controls you need to use (almost) any logic analyzer. You’ll learn how to set up a simple trigger, make measurements, and set things like sample rate or memory depth.

When I first graduated from college, I started as an Application Engineer for Agilent Technologies. Based in Austin, I supported computer companies like Dell, Compaq, HP, IBM, and Tandem. I helped their engineers set up million-dollar logic analyzer configurations to measure various PC busses.

I did embellish a tad during the introduction. Shown in the video is an HP 16500. While I did occasionally help program a trigger on these analyzers, my career really started with its successor, the HP 16700. Both were amazing analyzers for their time. It is mind-boggling to think that a small $150 USB-based device has very similar measurement capabilities to those old beasts.

Previously, I made a written Logic Analyzer introduction tutorial and benchmarked digitalWrite() with a Salee Logic 8. Contrary to what people have said, the LA2016 featured in this video does NOT use Salee’s excellent Logic software. However, the user interface is clearly copied from it.

See show notes on element14

Spectrum Analyzer Basics | Workbench Wednesdays

element14 Presents
2019-10-09

A spectrum analyzer displays signals in the frequency domain. To use one, you only need to know about four controls: reference level, center frequency, and resolution bandwidth. In this episode, see how to use a spectrum analyzer and determine the transmitting frequency of a device.

The example device is my microphone transmitter. It operates around 500 MHz with FM modulation. You’ll see how I step through the spectrum analyzer controls to find the exact frequency. At the end of the episode, I show some advanced measurements you can do with a modern spectrum analyzer. My favorite one is the demodulation. (more…)

Electronic Load Basics | Workbench Wednesdays

element14 Presents on YouTube
2019-09-18

During the Bench Power Supply basics video, I made use of my electronic load. An electronic load can sink current from power sources such as power supplies or batteries. Loads are useful to test a power supply’s design margin or verify a battery’s capacity. See how three different instrument options from ultra low-end to midrange to high-end compare. After this element14 Presents Workbench Wednesday video, you will understand how to use modes on an electronic load like constant current and constant resistance to make different measurements.

In the video, I compare three different types of tools: a $50 battery tester from eBay, BK Precision 8540 Electronic Load, and a high-end Rohde & Schwarz NGM202. They are all capable of acting as a constant current sink. In other words, you program the current and let the supply under test run. In the case of batteries, this mode is useful to test battery life. The 8540 and NGM202 both feature other capabilities like constant resistance which, as you can imagine, acts as an electronic resistor. The cool thing about using an electronic load as a power resistor is that some of them are capable of sinking up to 10s of amps.

After submitting the video to the producers, I realized I focused very heavily on batteries. More often, you use an electronic load to test power supply boards or modules. I wish I had shown those more, but it didn’t seem like it was missing until the end. So maybe in the future I can convert tools for measuring DC/DC power supplies? However, I did cover one topic significant to me. I show just how bad 9V batteries are, a topic which I like to come back to often. So I made sure to show off just how bad they work when driven past 100 mA. (It is terrible!)

Learn more at element14

Bench Power Supply Basics | Workbench Wednesdays

element14 Presents on YouTube
2019-08-28

A bench power supply makes powering circuits easy and safe. Learn how to adjust basic controls like voltage. Finally, see how “current limiting” works (and why you should use it.) See how you can use built-in series or parallel tracking to increase a bench power supply’s voltage or current output. Last, if you are in the market for a power supply, do not forget to add some leads like mini-grabbers, alligator clips, and banana plugs.

See more at element14

DCA Pro Transistor Tester Review | Workbench Wednesdays

element14 Presents on YouTube
2018-08-07

When it comes to transistors, there are only so many things a multimeter can measure. The DCA Pro from PEAK Electronics makes short work of testing parts like a transistor. This small device can determine pinout, component type, and essential parameters in a matter of seconds. Not only that, but it can be connected to a (Windows) PC and draw parameter curves.

 

Check out the video review to see how the device and software works. Then head over to the element14 page where you can download a zip file full of example parts I measured for you. Use the free DCA Pro software to open them.

You might also want to check out this MOSFET Curves post, which complements this video tutorial. Another resource you might find helpful on semiconductors, or transistors, is this post on MOSFET Myths.

See more on element14

7+ Python Engineering Modules for Electronics Engineers

Python is everywhere. Its capabilities continue to grow. Not only can you create simple scripts, but you can create full-blown applications with it. The core has been scaled down to run on 32-bit microcontrollers like the ESP32 and Adafruit Feather M0. You can even use Python engineer modules to design stuff like circuits. There are electronics Python modules that create schematics, simulate circuits, and make solving math a cinch. Here are some of the modules I found that make Python usable for (electronics) engineering.

Up front, make sure you have a functioning Python environment. Update the package manager “pip” since all of these electronics python modules rely on it. Speaking of dependences, you may need to also install third-party libraries for some of them. From what I can tell, these all should be platform independent. However, I only tested these electronic modules with 64-bit Windows.

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Hakko FX-888D Review

Pablo looks at one of the most popular soldering stations

My friend Pablo recently upgraded his firestarter iron to a Hakko FX-888D. Because of its popularity and his relative newness to the iron, I asked if he’d like to write up a review for it. You can follow him on twitter.

01-Hakko Iron and StandJust based on the color, the Hakko FX-888D seemed, at first, like it was a toy compared to other electronic tools and equipment. The color does make it easy to spot even if you are buried in a project. You can quickly find it because it stands out. The outside seems like plastic, but it is made from or encased in metal. Knowing that it was only a plastic enclosure made me feel like this will be with me for a long time.

I love how the iron holder is separate from the base. It easily can be placed anywhere in the work area. Also, keeping the base unit in one spot makes life so much easier. It gives the iron itself enough room so nothing nearby can accidentally be melted or burned by the iron.

The iron holder also has a convenient area for a cleaning wire and a cleaning sponge. I only wish that the opening for the cleaning wire was a bit bigger. As is, I regularly clean the tip using the same spot. Having the removable bottom makes it so easy to clean all the solder junk that collects at the bottom from the cleaning wire. If only the rubber legs were a bit wider, they would help keep the iron holder from sliding around my desk. (This could be just because of the type of tabletop I have it sitting on.)

Removable FX-888D tray

Removable FX-888D tray

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Raspberry Pi 4 Armchair Datasheet Evaluation

Are the performance improvements possible?

With the introduction of the Raspberry Pi 4, I dug into the announcement and datasheet while waiting for mine to arrive. Well, “datasheet” might be an exaggeration, but there is a list of the Raspberry Pi 4 tech specs available. That link gives a bullet item list of the main specs. In this post, I focus on these four:

  • Broadcom BCM2711, Quad core Cortex-A72 (ARM v8) 64-bit SoC @ 1.5GHz
  • Up to 4GB LPDDR4-2400 SDRAM (depending on model)
  • Gigabit Ethernet
  • 2 USB 3.0 ports; 2 USB 2.0 ports.

There is a lot of very cool stuff on this $35 board. (Amazing they have kept that price point!) Or even the 4 GB $55 board. Adding Bluetooth 5, H.265 AND H.264 decoding, USB-C connector (Power), and changing the SoC to a 28 nm process are all significant improvements.

But, being an engineer and a person on the Internet, I am required to nitpick, and armchair engineer this (now) released product (that I haven’t touched yet.) Without doubt there will be a number of benchmarks posted along with the release of the Pi 4. And I expect many of those only benchmark individual components. For example, I already saw graphs on the Gigabit Ethernet speed and USB 3.0 throughput, but not at the same time. As you will see in my datasheet evaluation, using two USB devices at the same time has a performance penalty.

First, what is new with the SoC?

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