Form vs. Function in Test

Input Voltage

–Jeff Child, Editor-in-Chief

JeffHeadShot

A couple months back I and the Circuit Cellar team attended ESC (Embedded Systems Conference) Boston. Having a booth was new for Circuit Cellar at ESC, so we were very pleased at the positive feedback from people who stopped by our booth—a mix of devoted long-time readers and new faces just learning about us. My thanks to those who became new subscribers on the spot. There are many good reasons for a technology editor like myself to attend tradeshows in our industry. Meeting with technology vendors—the people—face to face is the big one. I don’t care how convenient, realistic or powerful our various forms of electronic communication become. There will never—never ever—be any substitute for meetings done in person and the kind of conversation you can have face to face.

Another good reason to attend a show like ESC is to see the “stuff”—the embedded boards, chips, instruments and so on. I can write all day about the size, weight and power of a COM Express board. But it’s kinda nice to feel the size and weight by holding one in my hand. One type of gear that’s enormously important to see close up is test instrumentation products—oscilloscopes, logic analyzers, signal generators and so forth. Fortunately for me, ESC Boston had a nice cluster this year of test equipment exhibitors. Among these were Pico Technology, Rohde & Schwarz, Siglent Technologies, Tektronix and Teledyne LeCroy.

Like many of you, as an Electrical Engineering major in college I had a lot of EE labs. And I have to make a confession: Operating test equipment was never my strong suit. I remember my lab partners would seldom let me touch the oscilloscope once they caught on to my poor skills. I vividly remember a pair of them saying “Let’s have Jeff write the lab report. That’s at least something he’s good at.” Fast forward to my early years as a New Products Editor, and I sat through many press tour meetings. In those days, test equipment companies would make great efforts to lug their gear across country just to set it up and show me every last new feature of their new logic analyzer or scope.

At this year’s ESC Boston, it was fun seeing the state of the art test equipment on display. And I was able to glean a few insights. At today’s state of electronics technology, it’s quite feasible to have an all-in-one test system. But according to the vendors I talked to, there’s still a desire have a stand-alone box one can call an oscilloscope, for example. Also, even though touch-screen and push-button digital interfaces are mature technologies, many test customers still like feel of turning knobs when it comes to operating test gear.

Exemplifying what can be done with today’s technology, Pico Technology’s approach to test gear is to create compact, easily portable box-level systems. Instead of having a screen and arrays of controls, Pico Technology’s test systems instead interface with your laptop, so that laptop provides all the display and control needs for the equipment. Its latest example along those lines is its PicoScope 9300 Series of sampling oscilloscopes designed for measuring high-speed signals. The 9300 Series scopes provide 2 channels, 15 GHz bandwidth and 15 Terasample/s (64 fs) sequential sampling.

Rohde & Schwarz in contrast makes more traditional test gear, focusing on the high-performance end of the market. Its latest offering is its enhanced power-of-ten oscilloscope family with 10-bit resolution and large memory depth. According to the company, the power-of-ten oscilloscope families R&S RTB2000, R&S RTM3000 and R&S RTA4000 provide 10 times as much memory as comparable instruments and large 10.1” touchscreen displays.

Among the new products on display at Teledyne LeCroy’s booth at ESC Boston was what it claims as the industry’s first HDMI 2.1 Fixed Rate Link (FRL) Video Generator. FRL is the transport mode for HDMI 2.1 which enables transmission of uncompressed 8K video formats to reach link rates of up to 48 Gb/s.

All in all, my two days at ESC Boston were well spent. Aside from those test equipment vendors, there were a great mix of embedded hardware and embedded software tool vendors I met with at the show. I also sat in on a few presentations, including a great one called “ARM Trace: Kills Bugs Fast!” by IAR Systems’ Shawn Prestridge

This appears in the June (335) issue of Circuit Cellar magazine

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Denhac (Denver, CO, USA)

Denhac is a hackerspace on a mission to create and sustain a local, community driven, shared space, that enables education, experimentation, and collaboration, by applying the spirit of DIY to science, technology, engineering, and art.

Location 975 E 58th Ave, Unit N Denver, CO 80216
Members 45
Website Denhac.org

Alpha One Labs

What’s your meeting space like? 

It’s about 2,500 sq. ft. of commercial/warehouse/workshop space. We have an open shop floor area, bay doors, a classroom, an air-conditioned server room, and floorspace for several workstations specializing in various DIY areas.

What tools do you have in your space? 

  • Small OpenStack driven data center (four 72″ racks)
  • Cisco Networking workstation (for learning network engineering and infosec activities)
  • Textile workstation (sewing machines and USB driven embroidery machine) used for costuming, cosplay creation, etc.
  • 3D Printer workstation with Lulzbot printer
  • SeeMeCNC large format printer
  • Electronics workstation with oscilloscopes, breadboards, components, testing equipment, etc.
  • Soldering station
  • Small tools workstation (grinders, dremels, etc.),
  • Large format printer workstation,
  • Lasercutter (100watt),
  • Internet radio station (www.denhacradio.org) with a group going for a Low Power FM license (for running a community radio station)
  • Lots of racks for servers
  • 100 MB Internet

Are there any tools your group really wants or needs?

A metal forge, welding gear, carpentry gear, and CNC Tools.

Does your group work with embedded tech like Arduino, Raspberry Pi, embedded security, or MCU-based designs?

Yes, we teach classes on all of these (and more).

What are some of the projects your group has been working on?

Many and few, lots of individual projects. The group focuses more on collecting great tools for it’s members, and teaching classes on a broad range of topics (from making costumes, to hacking Arduino’s, to synthetic biology DNA hacking with bioblocks).

What’s the craziest project your group or group members have completed?

9′ Tesla coil. Also, a Steampunk flamethrower.

You mentioned a Low Power FM group earlier, can you tell us more about it? Are there other events or initiatives you’d like to talk about?

Yes, we’re just starting up a Low Power FM (LPFM) group that will be applying for a license to set up and run an FM community radio station at Denhac. We started a weekly Kids Coding Dojo class that teaches kids from ages six to fifteen how to code. (Accompanied by their parents.) We have a software defined radio hacking group (Radio Heads) that uses programs like GNUradio with SDR-capable radio kits and dongles to ‘listen in’ on the world. A BIG antenna is needed for that! We have a LockSport group that meets monthly and has some expert lock pickers. We have a 3D and LaserCutter printer group that meets as needed to teach members and the public how to use the equipment and to trade ideas on what to make next.

What would you like to say to fellow hackers out there?

Come and visit! We love visitors.

Want to know more about Denhac? Make sure to check out their website!

Show us your hackerspace! Tell us about your group! Where does your group design, hack, create, program, debug, and innovate? Do you work in a 20′ × 20′ space in an old warehouse? Do you share a small space in a university lab? Do you meet a local coffee shop or bar? What sort of electronics projects do you work on? Submit your hackerspace and we might feature you on our website!

Makelab Charleston (Charleston, SC, USA)

Makelab Charleston is a hackerspace for hobbyist and professionals who share common interests in technology, computers, science, or digital/electronics art. It provides an environment for people to create anything they can imagine: from electronics, 3D printing, and construction, to networking, and programming.

Location 3955 Christopher St, North Charleston, SC 29405
Members 24

Treasurer David Vandermolen will tell us something more about Makelab Charleston.

MakeLabCharleston

Tell us about your meeting space!

We started in a 500 sq. ft. garage, but took a step up and are currently renting a 900+ sq. ft. home that’s been renovated.  We now have the space for a electronic/soldering room that also has our 3-D printer. One other room is dedicated to power-type tools and our CNC machine that is still being built by our members.  The other spaces in the house are used for classes and member activities such as LAN parties.

What tools do you have in your space? (Soldering stations? Oscilloscopes? 3-D printers?)

Soldering stations, oscilloscopes, 3-D printer, power tools, large table-top CNC machine (in progress), and a rack server for the IT minded to play with.

Are there any tools your group really wants or needs?

A laser CNC, nice tables, and chairs .

Does your group work with embedded tech (Arduino, Raspberry Pi, embedded security, MCU-based designs, etc.)?

We have members that dabble in multiple areas so we try to provide classes on the technology people want to learn about and explore.

Can you tell us about some of your group’s recent tech projects?

Our most recent tech project has been a overhaul of our server system. Other projects include the CNC currently in progress. That’s been an ongoing project for about a year.

What’s the craziest project your group or group members have completed?

Probably the wackiest project we completed was actually, something not tech related at all, building a bed for Charleston Bed Races. We put together a Lego bed (not real Legos) complete with Lego man and all.

Do you have any events or initiatives you’d like to tell us about? Where can we learn more about it?

We list any events or classes we are doing or plan on doing on our Website. Just click on classes and events on the main page or go to the calendar tab.

What would you like to say to fellow hackers out there?

Makelab Charleston is about opening the world to information and sharing that information with the people in our community. The best way to do that is through teaching.

Show us your hackerspace! Tell us about your group! Where does your group design, hack, create, program, debug, and innovate? Do you work in a 20′ × 20′ space in an old warehouse? Do you share a small space in a university lab? Do you meet a local coffee shop or bar? What sort of electronics projects do you work on? Submit your hackerspace and we might feature you on our website!

A Workspace for Microwave Imaging, Small Radar Systems, and More

Gregory L. Charvat stays very busy as an author, a visiting research scientist at the Massachusetts Institute of Technology (MIT) Media Lab, and the hardware team leader at the Butterfly Network, which brings together experts in computer science, physics, and electrical engineering to create new approaches to medical diagnostic imaging and treatment.

If that wasn’t enough, he also works as a start-up business consultant and pursues personal projects out of the basement-garage workspace of his Westbrook, CT, home (see Photo 1). Recently, he sent Circuit Cellar photos and a description of his lab layout and projects.

Photo 1

Photo 1: Charvat, seated at his workbench, keeps his equipment atop sturdy World War II-era surplus lab tables.

Charvat’s home setup not only provides his ideal working conditions, but also considers  frequent moves required by his work.

Key is lots of table space using WW II surplus lab tables (they built things better back then), lots of lighting, and good power distribution.

I’m involved in start-ups, so my wife and I move a lot. So, we rent houses. When renting, you cannot install the outlets and things needed for a lab like this. For this reason, I built my own line voltage distribution panel; it’s the big thing with red lights in the middle upper left of the photos of the lab space (see Photo 2).  It has 16 outlets, each with its own breaker, pilot lamp (not LED).  The entire thing has a volt and amp meter to monitor power consumption and all power is fed through a large EMI filter.

Photo 2: This is another view of the lab, where strong lighting and two oscilloscopes are the minimum requirements.

Photo 2: This is another view of the lab, where strong lighting and two oscilloscopes are the minimum requirements.

Projects in the basement-area workplace reflect Charvat’s passion for everything from microwave imaging systems and small radar sensor technology to working with vacuum tubes and restoring antique electronics.

My primary focus is the development of microwave imaging systems, including near-field phased array, quasi-optical, and synthetic-aperture radar (SAR). Additionally, I develop small radar sensors as part of these systems or in addition to. Furthermore, I build amateur radio transceivers from scratch. I developed the only all-tube home theater system (published in the May-June 2012 issues of audioXpress magazine) and like to restore antique radio gear, watches, and clocks.

Charvat says he finds efficient, albeit aging, gear for his “fully equipped microwave, analog, and digital lab—just two generations too late.”

We’re fortunate to have access to excellent test gear that is old. I procure all of this gear at ham fests, and maintain and repair it myself. I prefer analog oscilloscopes, analog everything. These instruments work extremely well in the modern era. The key is you have to think before you measure.

Adequate storage is also important in a lab housing many pieces for Charvat’s many interests.

I have over 700 small drawers full of new inventory.  All standard analog parts, transistors, resistors, capacitors of all types, logic, IF cans, various radio parts, RF power transistors, etc., etc.

And it is critical to keep an orderly workbench, so he can move quickly from one project to the next.

No, it cannot be a mess. It must be clean and organized. It can become a mess during a project, but between projects it must be cleaned up and reset. This is the way to go fast.  When you work full time and like to dabble in your “free time” you must have it together, you must be organized, efficient, and fast.

Photos 3–7 below show many of the radar and imaging systems Charvat says he is testing in his lab, including linear rail SAR imaging systems (X and X-band), a near-field S-band phased-array radar, a UWB impulse X-band imaging system, and his “quasi-optical imaging system (with the big parabolic dish).”

Photo 3: This shows impulse rail synthetic aperture radar (SAR) in action, one of many SAR imaging systems developed in Charvat’s basement-garage lab.

Photo 3: This photo shows the impulse rail synthetic aperture radar (SAR) in action, one of many SAR imaging systems developed in Charvat’s basement-garage lab.

Photo 4: Charvat built this S-band, range-gated frequency-modulated continuous-wave (FMCW) rail SAR imaging system

Photo 4: Charvat built this S-band, range-gated frequency-modulated continuous-wave (FMCW) rail SAR imaging system.

Photo 5: Charvat designed an S-band near-field phased-array imaging system that enables through-wall imaging.

Photo 5: Charvat designed an S-band near-field phased-array imaging system that enables through-wall imaging.

Photo 5: Charvat's X-band, range-gated UWB FMCW rail SAR system is shown imaging his bike.

Photo 6: Charvat’s X-band, range-gated UWB FMCW rail SAR system is shown imaging his bike.

Photo 7: Charvat’s quasi-optical imaging system includes a parabolic dish.

Photo 7: Charvat’s quasi-optical imaging system includes a parabolic dish.

To learn more about Charvat and his projects, read this interview published in audioXpress (October 2013). Also, Circuit Cellar recently featured Charvat’s essay examining the promising future of small radar technology. You can also visit Charvat’s project website or follow him on Twitter @MrVacuumTube.