One Protocol to Rule Them All!? – #34

The USB Type-C brings a lot of protocols into one physical connector, but is there room for one protocol to handle all our IO needs? Mike Hoffman and Daniel Bogdanoff sit down with high speed digital communications expert Jit Lim to find out.

USB Type-C brings a lot of protocols into one physical connector, but is there room for one protocol to handle all our IO needs? Mike Hoffman and Daniel Bogdanoff sit down with high speed digital communications expert Jit Lim to find out.


0:00 This is Jit’s 3rd podcast of the series

1:00 We already have one connector to rule them all with USB Type-C, but it’s just a connector. Will we ever have one specification to rule them all?

2:00 Prior to USB Type-C, each protocol required it’s own connector. With USB TYpe-C, you can run multiple protocols over the same physical connector

3:00 This would make everything more simple for engineers, they would only need to test and characterize one technology.

3:30 Jit proposes a “Type-C I/O”

4:00 Thunderbolt already allows displayport to tunnel through it

4:30 Thunderbolt already has a combination of capabilities. It has a display mode – you can buy a Thunderbolt display. This means you can run data and display using the same technology

6:30 There’s a notion of a muxed signals

7:00 The PHY speed is the most important. Thunderbolt is running 20 Gb/s

7:15 What would the physical connection look like? Will the existing USB Type-C interface work? Currently we already see 80 Gb/s ports (4 lanes) in existing consumer PCs

9:20 Daniel hates charging his phone without fast charging

9:40 The USB protocol is for data transfer, but is there going to be a future USB dispaly protocol? There are already some audio and video modes in current USB, like a PC headset

11:30 Why are we changing? The vision is to plug it in and have it “just work”

12:00 Today, standards groups are quite separate. They each have their own ecosystems that they are comfortable in. So, this is a big challenge for getting to a single spec

13:15 Performance capabilities, like cable loss, is also a concern and challenge

14:00 For a tech like this were to exist, will the groups have to merge? Or, will someone just come out with a spec that obsoletes all of the others?

15:30 Everyone has a cable hoard. Daniel’s is a drawer, Mike’s is a shoebox

16:30 You still have to be aware of the USB Type-C cables that you buy. There’s room for improvement

17:30 Mike wants a world of only USB Type-C connectors and 3.5mm headphone jacks

18:30 From a test and measurement perspective, it’s very attractive to have a single protocol. You’d only have to test at one rate, one time

19:30 Stupid questions

The Huge Challenge of Testing USB 3.2 – #33

USB 3.2 doubles the data rate of previous USB specs, but makes the testing process significantly harder. Find out why in this electrical engineering podcast.

USB 3.2 testing is darn hard! We talk compliance test specs, USB 3.2 testing BKMs, and pre-spec silicon. Guest Jit Lim sits down with Mike Hoffman and Daniel Bogdanoff to talk about the new difficulties engineers are facing as they develop USB 3.2 silicon.



In the last electrical engineering podcast, we talked about how USB 3.2 runs in x2 mode (“by two”)

This means there’s a lot of crosstalk. The USB Type C connector is great, but its small size and fast edges means crosstalk is a serious concern.

When we test USB, we want to emulate real-world communications. This means you have to check, connect, and capture signals from four lanes.

For testing Thunderbolt you always have to do this, too.

Early silicon creators and early adopters are already creating IP and chips for a spec that isn’t released yet.

2:00 They’re testing based on the BKM (Best Known Method)

3:30 Jit was just at Keysight World Japan, where many people presented BKMs for current technologies. Waiting for a test spec to be released is not an excuse for starting to work on a technology.

4:50 How many companies are actually developing USB 3.2 products? The answer isn’t straightforward – the ecosystem is very complex and there are multiple vendors for a single system (like a cable).

6:30 Many USB silicon vendors will develop an end-product and get it certified to prove that their silicon will work. They then sell the silicon and IP to other companies for use in their products.

7:50 Daniel listened to an interesting podcast about how Monoprice reverse engineers complex products and sells them for cheaper:

9:40 There are some BNC cables at the Keysight Colorado Springs site that were literally wire pulled and built in the building.

10:00 Has anything changed as USB technology advances? There are a lot of new challenges – multiple challenges, retimers, multiple test modes

Testing retimers is nontrivial, they are full receivers and full transmitter.

11:30 When a new spec is developed, what does that look like? How far does the test group go when setting a new spec?

The spec doesn’t look at how to test, it just looks it what it should do.

Then, there’s a compliance test specification (CTS). This is developed by a test group, that looks at how things should be tested.

So, there are two groups. the first asks “what should the spec be?” and the second asks “how do we test that group?”

13:30 How many people are testing USB 3.2? Even though the compliance test specification is not developed yet? There are non being shipped, but there is a lot of activity!

14:30 What are the main challenges? Basics. When you have 10 Gbps over copper on a PCB, people are failing spec! There are issues with some devices passing only intermittently. Especially over long cables and traces.

15:45 Cheap PCBs make things even more tricky. So, there’s very sophisticated transmitter equalization and even moire sophisticated receiver equalization. It’s crucial to keep the low cost PCB material and processes to keep the overall end-product cost low. Using higher end materials would dramatically increase the cost of consumer products.

17:30 The first TV Mike bought was after his internship at Intel. He bought a $30-ish 1080i TV for $1600. Now, you couldn’t give away that TV.

18:30 Stupid questions for Jit:
What is your favorite national park and why?
What is your favorite PCB material and why?





USB 3.2 + Why You Only Have USB Ports On One Side of Your Laptop – #32

USB 3.2 DOUBLES the data transfer capabilities of previous USB specifications, and could mean the end of having USB ports on just one side of your computer. Find out more in today’s electrical engineering podcast with Jit Lim, Daniel Bogdanoff, and Mike Hoffman.

USB 3.2 DOUBLES the data transfer capabilities of previous USB specifications, and could mean the end of having USB ports on just one side of your computer. Find out more in today’s electrical engineering podcast with Jit Lim, Daniel Bogdanoff, and Mike Hoffman.


Jit is the USB and Thunderbolt lead for Keysight.

USB 3.2 specifications were released Fall 2017 and released two main capabilities.

USB 3.2 doubles the performance of  USB 3.1. You can now run 10Gb/s x2. It uses both sides of the CC connector.

In the x2 mode, both sides of the connectors are used instead of just one.

The other new part of USB 3.2 is that it adds the ability to have the USB silicon farther away from the port. It achieves this using retimers, which makes up for the lossy transmission channel.

Why laptops only have USB ports on one side! The USB silicon has to be close to the connector.

If the silicon is 5 or 6 inches away from the connector, it will fail the compliance tests. That’s why we need retimers.

USB is very good at maintaining backwards compatibility

The USB 3.0 spec and the USB 3.1 spec no longer exist. It’s only USB 3.2.

The USB 3.2 specification includes the 3.0 and the 3.1 specs as part of them, and acts as a special mode.

From a protocol layer and a PHY layer, nothing much has changed. It simply adds communication abilities.

Who is driving the USB spec? There’s a lot of demand! USB Type C is very popular for VR and AR.

There’s no benefit to using legacy devices with modern USB 3.2 ports.

There’s a newly released variant of USB Type C that does not have USB 2.0 support. It repurposes the USB 2 pins. It won’t be called USB, but it’ll essentially be the same thing. It’s used for a new headset.

USB Type C is hugely popular for VR and AR applications. You can send data, video feeds, and power.

Richie’s Vive has an audio cable, a power cable, and an HDMI cable. The new version, though, has a USB Type-C that handles some of this.

USB 3.2 will be able to put a retimer on a cable as well. You can put one at each end.

What is a retimer? A retimer is used when a signal traverses a lossy board or transmission line. A retimer acquires the signal, recovers it, and retransmits it.

It’s a type of repeater. Repeaters can be either redrivers or repeaters. A redriver just re-amplifies a signal, including any noise. A retimer does a full data recovery and re-transmission.

Stupid Questions:
What is your favorite alt mode, and why?
If you could rename Type-C to anything, what would you call it?




BONUS: EEs as Astronauts – Audio Exclusive

Astronaut Kay Hire answers the question: “What advice would you give to an engineer hoping to become an astronaut?”

Astronaut Kay Hire answers the question: “What advice would you give to an engineer hoping to become an astronaut?”


Weather CubeSats – #30

We have surprisingly little knowledge of weather. When specifically does a cloud rain? How do these clouds form? We don’t have good answers to these questions. Getting those answers is an electrical engineering problem – one that a handful of professors and NASA are solving with CubeSats.

Historically, we’ve used large satellites and ground-based systems to track weather patterns, but CubeSat arrays are becoming a viable option. In this episode, Daniel Bogdanoff sits down with the leading researchers in this area to hear about the challenges and advancements being made in this area.

We have surprisingly little knowledge of weather. When specifically does a cloud rain? How do these clouds form? We don’t have good answers to these questions. Getting those answers is an electrical engineering problem – one that a handful of professors and NASA are solving with CubeSats.

Historically, we’ve used large satellites and ground-based systems to track weather patterns, but CubeSat arrays are becoming a viable option. In this episode, Daniel Bogdanoff sits down with the leading researchers in this area to hear about the challenges and advancements being made in this area.


Charles Norton – JPL Engineering and Science Directorate POC
Joel T Johnson – ECE Department Chair and Professor at The Ohio State University
Christopher Ball – Research Scientist at The Ohio State University
Dr. V. Chandrasekar (Chandra) – ECE Professor at Colorado State University
Eva Peral – Radar Digital Systems Group Supervisor at JPL



Space is changing. Big, expensive satellites used to be our only option. But, as you’ve probably heard on this podcast, when it comes to technology the world is always shrinking – and satellites are no exception. And that’s what we’re exploring today, specifically, the way cubesats (miniature satellites) are revolutionizing the way we look at earth’s weather.

Hi, my name is Daniel Bogdanoff, and welcome to EEs Talk Tech. In our last episode, I brought you all along with me to Wallops flight facility in Virginia for a rocket launch. It was an eye-opening experience for me, and I wanted to cover more than was reasonable for a single episode. So today, we’re blending the style of last episode and our standard interview-style podcast. I sat down with some EE professors from Ohio State University and Colorado State University to talk about their cube sat projects – all of which monitor weather using radiometers or radar and are pretty high tech.

I also apologize in advance for the background noise during the interviews, I’ve done the best I can to minimize the noise and voiceover parts I feel are hard to hear. I’ve also used clips from their NASA TV presentations wherever possible.

Let’s get started, and hear a little bit about the advantages of CubeSats from Charles Norton.

Advantages of CubeSats [1:05]

Cubesats are nice not just because they’re cheaper and smaller. Thanks to the miniaturization of new technologies in both their physical size and their power consumption, we can deploy more systems, more rapidly, and at a lower cost. They also require smaller teams to develop and operate, and can even have higher measurement accuracy than existing assets.

CubeRRT [3:51]

At its core, CubeRRT is all about making radiometry measurements better by processing out man made emissions – leaving only the earth’s natural emissions.

From NASA: “Microwave radiometers provide important data for Earth science investigations, such as soil moisture, atmospheric water vapor, sea surface temperature and sea surface winds. Man-made radiofrequency interference (RFI) reduces the accuracy of microwave radiometer data, thus the CubeSat Radiometer Radio Frequency Interference Technology Validation (CubeRRT) mission demonstrates technologies to detect and remove these unwanted RFI signals. Successful completion of the CubeRRT mission demonstrates that RFI processing is feasible in space, high volumes of data may be processed aboard a satellite, and that future satellite-based radiometers may utilize RFI mitigation.”

TEMPEST-D [8:00]

Instead of having a big satellite sitting in geosynchronous orbit, an array of CubeSats can be put in orbit such that they each pass over the same spot at set intervals. With some careful calibration, differences in the measurement equipment gets normalized out and they get good weather data.

From JPL: “TEMPEST-D is a technology demonstration mission to enable millimeter wave radiometer technologies on a low-cost, short development schedule. The mission … reduces the risk, cost, and development duration for a future TEMPEST mission, which would provide the first ever temporal observations of cloud and precipitation processes on a global scale.  For TEMPEST-D, JPL developed a mm-wave radiometer payload that operates at five channels from 89 to 182 GHz and fits in a 4U volume within the 6U CubeSat.”

RainCube [11:47] & the Origami Antenna

From JPL: “RainCube (Radar in a CubeSat) is a technology demonstration mission to enable Ka-band precipitation radar technologies on a low-cost, quick-turnaround platform. RainCube developed a 35.75 GHz radar payload to operate within the 6U CubeSat form factor. This mission will validate a new architecture for Ka-band radars and an ultra-compact lightweight deployable Ka-band antenna in a space environment to raise the technology readiness level (TRL) of the radar and antenna from 4 to 7 within the three year life of the program. RainCube will also demonstrate the feasibility of a radar payload on a CubeSat platform.”

Foldable Antenna [12:20]

1.5U volume, Ka-band 35.75 GHz RADAR antenna.

Why Measure Weather from Space? [15:00]

These are just a few of the cubesat projects that went up on the OA9 rocket launch. To hear more about that, check out EEs Talk Tech electrical engineering podcast episode #29 – The Long Road to Space.


The Long Road to Space – #29

I went for a rocket launch, and stayed for the science. Have you ever wondered what it actually takes to get a rocket into space? And why we go there at all?

I went for a rocket launch, and stayed for the science. Have you ever wondered what it actually takes to get a rocket into space? And why we go there at all? I hadn’t. Come with me on a behind the scenes tour of Wallops Flight Facility. Space balloons, sounding rockets, and a bonafide rocket launch!


Thank you again to Laurie Bonneau, John Mitchell, and John Huntington, NASA, and Orbital ATK/Northrup Grumman for letting me use your amazing photos!

Check out Laurie B’s Flickr page here

John M’s Flickr page here

and John Huntington’s coverage of the launch.

Keysight oscilloscope probe promotion here.


0:00 – Getting to Wallops Flight Facility
4:40 – “What’s on Board” Science Briefings
8:03 – CubeSats
9:32 – Concrete in Space?
11:10 – Cold Atom Laboratory and Bose Einstein Condensates

15:09 – Launch Pad 0A Visit

15:50 – Horizontal Integration Facility (HIF)

19:29 – Range Control Center

21:23 – Space Balloons

24:25 – Sounding Rocket Machine Shop and Test Lab

28:53 – Astronaut Kay Hire

31:04 – OA9 rocket launch day!


On the Virginia coast, hours away from any major airport, you’ll find what appears to be a sleepy little town. It’s not a tourist town or a beach town, that’s further down the road. Driving through, you’ll see an abandoned roller rink and billboards for opioid abuse programs, a retro country radio station, and the seafood restaurant in the next town over. There’s a single diner is nestled in a gas station, right across the street from a house with a half dozen American flags and a huge “support our troops” sign in the front yard.

But when you drive a little further, you might start to wonder if there’s more to this town than meets the eye. Down the road from the diner is the smallest Lockheed Martin building I’ve ever seen. Drive a minute longer, and the forest clears.

Immediately, you know there’s more to this town.

Your eyes are first drawn to giant satellite communication antennas, and then to radar installations and what look to be airplane hangers emblazoned with the NASA logo. Of course, all of this is surrounded by fences with stern warnings for trespassers and loiterers – keeping gawkers at bay, leaving them to wonder what’s going on in there.

Thanks to you, who follow us on YouTube and the EEs Talk Tech podcast, I wasn’t left to wonder. And now, neither are you.

NASA granted me and select others special access to tour the facilities.

So, what is this place?

Turns out, it’s a lot of things.

The most exciting role of this place, for me anyways, is that it’s the site of Antares rocket launches.

Twice per year, this sleepy, backwoods town wakes up with a start. The world’s top engineers, scientists, and researchers flock to the town. Wide-eyed high school students working the counter at the lone diner try desperately to feed a line of people that stretches out the door. The hotels in the area are completely booked.

Because this weekend, we’re going to space.

Have you ever wondered what makes a place like this tick? There’s an entire economy and ecosystem dedicated to keeping it afloat.

I always thought the rocketry aspect was the main attraction, but never gave much thought to the actual point of it all. Space is pretty cool, but what does humanity actually gain by getting there?

That’s what we’re going to look at today. We’re going to explore the science. Go past those warning-ridden fences. Take a look at some of the projects that get a lot of press, and some that are less glamorous. Then we’re going to look at how those projects get deployed. And yes, that includes a rocket launch. Here we go.

Day 1. It’s Friday, May 18th. For me, it means travel day. One of the reasons Wallops Flight Facility is a great location is that there’s, quote “virtually unimpeded airspace.” For visitors, this means you have to drive from your major airport of choice for at least a couple hours. So, it’s gonna be a long day. I figure I’ll leave home around 7 AM and arrive at my hotel roughly 16 hours later.

It’s a long day for domestic travel, but what’s a guy to do? As the plane doors close at the gate in Denver, I find out the launch has been delayed 24 hours for additional spacecraft inspections. It’s too late to get off the plane, so I shrug, text my wife that I’m going to be another day on the road, and mentally score one point for fate. Fate 1, Daniel 0. From what I hear, though, delayed launches are just part of the process. No one wants a failed launch.

When I land in DC it’s raining pretty hard, and I decide I don’t really want to cram in a few hours of driving. So I scramble to re-arrange lodging, and catch a movie before bed. Take that, fate.

Day 2. Saturday. I drive from DC to the coast, and start to wonder if I’m really in the right place. I check my phone map, and it says I’m on track. Once the woods clear and I see the com arrays and the hangers with the NASA logo, I know I’m in the right place. After showing a couple forms of ID to an armed federal agent, I get my pass and am ushered into the day’s event – the “what’s on board” mission briefing.

This is when I start to think about more than just the rocketry. Scientists from around the country show off their experiments, which have been loaded into the Cygnus spacecraft, attached to the Antares rocket, and are about to be delivered to the ISS. They’re being delivered on the OA-9 cargo mission, which is why I’m in town. OA9 is completely run by Orbital ATK. Orbital ATK is one of the two commercial companies with NASA launch contracts. The other is SpaceX. But, don’t compare them to Space X, it’s a bit of a touchy subject around here.

Back to the experiments – which NASA likes to call “investigations.” Technically, an experiment’s goal is to prove or disprove a hypothesis, and an investigation is more about gathering data. Potayto potahto.

There are over a thousand kilograms of investigations headed to the ISS this weekend. Access to space gives scientists and engineers the ability to test things that simply aren’t possible on earth. There’s the height advantage – we can look at more of the earth at once without the curvature getting in the way. There’s the obstruction advantage – we can see things without the earth’s atmosphere getting in the way. And there’s the gravity advantage – namely, we can sustain a microgravity environment for more than a dozen seconds.

The investigations being presented also showed me the breadth and diversity of investigations taking place in space. To give you a taste, here are my personal favorites that are a part of this mission. Full disclosure, I’ll likely be too casual with some of these terms, so feel free to correct me in the YouTube comments or at EEs Talk

There’s a DNA/RNA sequencing kit designed to find unknown microbes on the international space station. It’s called “Biomolecule Extraction and Sequencing Technology” investigation, or “BEST” for short. In my opinion, this is the best acronym.

They can find most of the bugs on the ISS with their current, culture-based processes, but this kit will allow them to find other microbes. It will also let them track mutations of known microbes – apparently spaceflight causes genetic, epigenetic, and transcriptomic changes.

There’s also a sextant for navigation practice, and some medical tools to monitor astronaut’s eyesight. Apparently long term spaceflight messes with people’s eyes. You know, they’ve seen things…

There’s a liquid separation tool that uses capillary forces to separate flowing liquids. Normally, you’d have to let liquids settle (think oil – vinegar salad dressing), but this does it while liquids flow. Speaking of salad dressing, there’s an enhanced vegetable grower on board, too.

Astronauts will record the flavor and texture of the plants, and their results will be compared to a control sample in Houston. Apparently, even salad is an investigation in space.

Another interesting part of the payload is an array of CubeSats – dubbed “CubeRRT”-  aimed at measuring the earth’s RF emissions to mitigate environmental noise.  Microwave Radiometers, a tool used to gather environmental data like seawater salinity, temperature, and humidity are extremely sensitive to the emissions. Because of earth noise and increased spectrum use, the radiometer measurements are becoming noisier and noisier – and will possibly become unusable in the not-to-distant future. The goal of these cubesats is to monitor these environmental factors and create a system to remove noise in real-time. When I sat down with the professors responsible for the program, they mentioned that the emissivity of water was a deciding factor in earth noise. Sensitivity to water vapor peaks around 24 GHz, which is right in the middle of the allocated spectrum for these tools. Vegetation and soil moisture also play a role. So, CubeRRT will be able to measure earth-noise from 6 GHz to 40 GHz. If you want to hear more about this topic, I sat down for an interview with this team that will be a future podcast – assuming my recording worked out.

There was also a concrete project – concrete formation is a pretty well defined terrestrial science, but it’s not well defined in a microgravity environment. Astronauts will mix concrete, let it set, and send it earthward for analysis. The findings of this project are the first stages of exploring construction options for the moon and mars. Can you use Martian soil to make concrete? We’ll see.

Finally, the coldest known spot in the universe will soon be the ISS. Led by Jet Propulsion Laboratories, five different research teams will share time on this project – the Cold Atom Laboratory which is designed to cool gas particles to “like one-tenth of a billion of a degree above absolute zero.” (Robert Shotwell). One team, led by Nobel prize winning physicist Eric Cornell, will study Bose Einstein condensates.

This was a new thing to me, so I did a little digging. A Bose Einstein condensate is a quantum state theorized by Bose and Einstein, and realized in 1995 by the same Dr. Eric Cornell we were just speaking of. Essentially, if you super cool a gas – like super-duper cool it – the atoms start to increase in size and behave as waves. Eventually, the size of these wave-atoms becomes larger than the average distance between wave-particles – meaning they’ll begin to interact. At a certain point, all of the wave-particles (known as Bosons) settle in the same quantum state and form one big, happy quantum wave, known as a Bose-Einstein condensate.

The problem with this, is that they’re really, really hard to create. One of the reasons for this is gravity. Hence, the Cold Atom Lab. The micro-gravity environment of the space station will allow Dr. Cornell and his associates to reach temperatures colder than that of earth. All without needing time from astronauts. Pretty cool!

Sorry, couldn’t resist.

Clearly, there’s a huge breadth of projects invested in this launch.

After the briefing, its back to the hotel to get some work done – it is a workday after all. The day concludes with a dinner with some of the other attendees. Because, what engineer doesn’t love a meal with a bunch of complete strangers?

In a public setting, I almost always feel like the biggest geek in the room. Sometimes that’s fun, most of the time it’s not – I’m sure a lot of you can relate. But this was different. There’s something about being a room full of other self-proclaimed space geeks that really made me feel at home.

After a little too much of the good luck ice cream that Orbital ATK orders from a local shop – it’s chocolate with chili powder and cinnamon, which is surprisingly ok – it’s time to rest up for day 2.

Day 2 starts at 8AM. That’s not bad unless you factor in a couple hour time change for me. I quickly wake up, though, as we all hop on a bus to go out visit the rocket. Naturally, we aren’t able to go right up to it, but we’re pretty darn close. Closer than you’d normally get to a fully-primed rocket, anyways. “Surreal” is a term thrown around a lot by launch 1st timers like me, and though it’s cliché, it’s probably the best word to describe the feeling. It reminds me a bit of my childhood, when I could get a glimpse of the Matterhorn at Disneyland while driving to Grandma’s house on the 5. There’s this academic knowledge of a whole group of people living in their little complex, separated world, and the sight of the monument is just the surface of it.

After 15 minutes of staring, it’s time to head over to what becomes my favorite stop of the tour – the horizontal integration facility, also known as the HIF.

We got to get up close and personal with OA10, the next launch scheduled for a fall launch. Naturally, it’s only partially assembled. The HIF is the place that takes all the pieces and parts from around the world and connects them into one cohesive vehicle. Due to the presence of “active ordinance” and “export controlled technology,” all wireless devices had to be left outside and our picture taking was limited. So, I can’t show you the advanced piping and routing that is the backbone of a rocket engine, but think copper-shiny-jet-engine-plumbing on steroids.

I was surprised by how much coordination was involved in the rocket and assembly.

Again, it was fascinating to me to see so many teams working on so many discrete, but integrated projects. And to watch it all come together in this sleepy backwoods town feels a bit ironic.

A quick pit stop for a press conference, and it’s off to the Range Control Center.

The RCC acts as a sort of mission control for launches and other on-site missions. This is where I start to see the work of yet another set of behind-the-scenes teams. Meteorologists to check winds and weather, radar controls to monitor air & boat traffic (the previous launch got scrubbed by a small boat that came too close), technical teams to handle copious amounts of real-time data and processing, specialists manning custom rocket system monitoring software, and more. The ability to photograph any of this was again limited, but it looked something like the systems you’d see bad guys working on in a James Bond dam-hostage situation.

Each of these teams come together and repeatedly rehearse each launch under varying circumstances and environments so that they’re ready to handle any surprises that could pop up on launch day. It’s humbling to think that each of these workstations essentially represents a mission-critical team.


We hop back on the buses and head over to the space balloon research center.


Space balloons sound a bit counterintuitive, after all, how can a balloon float if there’s no atmosphere? Well, they go up to 120,000 feet – so not really into space which more-or-less starts around 100 km. It’s called near space. These balloons are described by Gabe Garde, Mission Operations Manager for the balloon program, as Football field-sized, ultra-sonically heat-welded trashbags. Really. They’re huge .2-.8 mil thick plastic bags that can stay in the sky for weeks or months. That’s about the thickness of a sandwich bag, but the plastic is a little sturdier. Sometimes referred to as the B-line to space, balloons are the quickest and most cost efficient route to near space.

They can also be launched from nearly anywhere on the globe. Gabe, for example, has spent a collective year living in Antarctica for balloon missions. Why Antarctica?

Remember when we found the giant hole in the ozone layer over Antarctica? Space balloons were the vehicle for those measurement tools. The generally-flat geometry of the universe was also confirmed by a balloon-borne investigation.

These balloons have recently been with a giant gimbal, known as the “Wallops arc second pointer”

We then float out of the balloon research center and file into a giant machine shop – part of the Sounding Rocket Lab, where we meet this fine fellow. [6420]



Nose cone that launches off the rocket to expose scientific equipment, coated with a spray-on silicon as a heat-deterrent

One of the benefits of sounding rockets is the possibility for extremely quick turnaround times. How fast?

9 years! That makes me feel better about the timing of some of my projects.

There are also some electrical test rooms with racks full of equipment and the wrong-colored oscilloscopes, in my opinion anyways. I did a little probing into what electronics they’re using, but didn’t get much info beyond the fact that the sounding rockets use an RS-485 communications bus. I’ll have to bug them a little more next time.

After a couple more technical presentations, we have a little chat with Astronaut Kay Hire. She talks through a lot of the processes, activities, and emotions astronauts go through – they don’t deviate much from what you’ll find in a standard astronaut interview. But, there was a moment that stood out.

This seems like a pretty obvious statement, but being surrounded by the teams of people working on slivers of the rocket & surrounding projects really drives this point home.

She also talked a little bit about navigating around space junk and debris:


After all, the launch already got pushed back a day because they needed to run more tests. So, with our official tour over for the day, we head out to get tacos (which are pretty good by East-coast standards), and worry about Kay’s parting words. There’s also so debate about whether or not it’s worth pulling an all-nighter into day 3.

Why pull an all-nighter? Day 3 starts at 1:30 AM. I’m not in the all-nighter camp – I had my share in college, so, I head back to the hotel for a nap – wake up at 1:30, munch gas station donuts and coffee, and drive to meet our bus – in the pouring rain – not a good sign. I expect a pretty subdued bus crowd, given the time and the weather, but the energy is palpable – you can feel the anticipation. Federal guards escort us and the media to the launch-viewing area. As the crow flies, we’re roughly 2 miles away from the rocket, which is as close as anyone gets to these things. I set up my camera gear alongside some other folks, and glance down the line of media photographers. There’s easily over a million bucks worth of camera gear here. Loudspeakers stream the coms, and we start to get worried. The weather folks over at the Range Control Center don’t like what they are seeing, and move the launch target time to the very end of the 5-minute window. We hear words like “anomaly” and “verifying the authenticity of the fire alarm” and get more nervous. I get more coffee and donuts from the catering tent and wait. Apparently donuts are my nervous food.

Tee minus 12 minutes, and it’s time for the go-no go for launch poll. Everyone goes quiet as the work through the countdown. Over the loudspeakers, we hear

The group collectively releases a sigh of relief, some cheer. We’re launching today. We buckle down for the 12 minute wait.

30 seconds left, and all we can do is fidget and wonder if our camera settings are correct. They say that you shouldn’t try to photograph your first launch – you should just enjoy it and let the million bucks in camera gear handle the pictures. I like a challenge so I take a stab at it, but I recommend that if you go see a launch you let other people do the filming.

10 seconds. The iconic countdown starts…

Here’s what it sounds like when you can see the launch, but before the sound arrives (a good 14 seconds before the sound hits us. The night sky turns to daylight, and the rocket starts to make its way up. I’m struck by how slow it looks at first, and how the 200 ft flame does a weird, glitchy dance. It passes through the clouds.

Then the sound hits us. It’s xdB louder than us talking & cheering. You can feel it, like less bassey fireworks.

The sound slowly fades to a low rumble as the rocket re-appears above the clouds. A few minutes later, the light cuts out. Because stage 2 uses solid-fuel, there’s no throttle. So the Orbital ATK telemetry team calculates the velocity and position of the craft. With this telemetry data, they know how long they have to wait before igniting the second stage. This ensures that they only need minimal adjustments to get sync with the ISS.

Adjustments require fuel, which means weight, which means cost. And, private space is all about cost-per-pound into orbit. That’s why the launch window was only 5 minutes, it was a cost play. Cost was also a big factor in the decision to retire the space shuttle.

Stage two kicks in, the brightest star in the sky. Slowly, it fades out and is gone

It’s now past 5AM and people start to pack up, tired, but happy. The firefighting teams hop in their firetrucks and drive towards the launch pad. I can only imagine the relief of the teams that have spent months and years on these systems. You’d never know, though, as their voices ring out over the loudspeakers, working through their post-launch checklists. They are a little more casual, though, a little bit of pride and relief sneaking past their professional masks. There are some anomalies, though, so it may still be a long day for a few folks.

After this 2 ½ day space bonanza, I say goodbye to my new friends and start the long trip home to Colorado. While driving across the massive Chesapeake Bay Bridge, and flying over the Rocky Mountains, I have some time to think about something Astronaut Kay Hire said in her talk. She said this:

I can’t help but resonate with this in the moment. I’m driving over a 4.3 mile steel bridge – when it was built it was the largest over-water steel structure. I’m flying over half of the USA, a trip would take weeks without technology. Then, I think back to the rocket launch. Months, years, and careers were spent making that launch happen. Even more months and years of time was dedicated to the cargo. Even more time dedicated to having a place in space to put it all. Teams upon teams, collective lifetimes of effort – all boiled down to a single, fiery, loud instant.

I dwell on Kay’s statement. “We’re not   to fly in space. But we’re built to adapt.” Clearly. That’s why we have spacesuits, 4 mile long bridges, airplanes, and sleepy towns that transform into technology centers. So I agree. We’re not built to fly in space. But maybe, maybe we were made for it.

Most of the big white coms arrays belong to the NOAA Command and Data Acquisition Station. NOAA, founded by Nixon, has a suite of environmental monitoring satellites. These satellites need to be nudged periodically to remain in orbit, and they send down an obscene amount of data that needs to be collected and distributed.

The next time your local weather forecast is accurate, the data that enabled it probably came through this site.


DDR5 and 3D Silicon – #25

DDR5 marks a huge shift in thinking for traditional high-tech memory and IO engineering teams. The implications of this are just now being digested by the industry, and opening up doors for new technologies. In today’s electrical engineering podcast, Daniel Bogdanoff and Mike Hoffman sit down with Perry Keller to discuss how engineers should “get their game on” for DDR5.

“You reach critical certain thresholds that are driven by the laws of physics and material science” – Perry Keller

DDR5 marks a huge shift in thinking for traditional high-tech memory and IO engineering teams. The implications of this are just now being digested by the industry, and opening up doors for new technologies. In today’s electrical engineering podcast, Daniel Bogdanoff and Mike Hoffman sit down with Perry Keller to discuss how engineers should “get their game on” for DDR5.



Sign up for the DDR5 Webcast with Perry on April 24, 2018!


00:20 Getting your game on with DDR5

LPDDR5 6.4 gigatransfers per second (GT/s)

“You reach critical certain thresholds that are driven by the laws of physics and material science” – Perry Keller

1:00 We’re running into the limits of what physics allows

2:00 DDR3 at 1600 – the timing budget was starting to close.

2:30  With DDR5, a whole new set of concepts need to be embraced.

3:00 DesignCon is the trade show – Mike is famous for his picture with ChipHead

4:00 Rick Eads talked about DesignCon in the PCIe electrical engineering podcast

4:40 The DDR5 paradigm shift is being slowly digested

4:50 DDR (double data rate) introduced source synchronous clocking

All the previous memories had a system clock that governed when data was transferred.

Source synchronous clocking is when the system controlling the data also controls the clock. Source synchronous clocking is also known as forward clocking.

This was the start of high speed digital design.

At 1600 Megatransfers per second (MT/s), this all started falling apart.

For DDR5, you have to go from high speed digital design concepts to concepts in high speed serial systems, like USB.

The reason is that you cant control the timing as tightly. So, you have to count on where the data eye is.

As long as the receiver can follow where that data eye is, you can capture the information reliably.

DRAM doesn’t use an embedded clock due to latency. There’s a lot of overhead, which reduces channel efficiency

DDR is single ended for data, but over time more signals become differential.

You can’t just drop High Speed Serial techniques into DDR and have it work.

The problem is, the eye is closed. The old techniques won’t work anymore.

DDR is the last remaining wide parallel communication system.

There’s a controller on one end, which is the CPU. The other end is a memory device.

With DDR5, the eye is closed. So, the receiver will play a bigger part. It’s important to understand the concepts of equalizing receivers.

You have to think about how the controller and the receiver work together.

Historically, the memory folks and IO folks have been different teams. The concepts were different. Now, those teams are merging

DDR5 is one of the last steps before people have to start grappling with communication theory. Modulation, etc.

Most PCs now will have two channels of communication that’s dozens or hundreds of bits wide.

What is 3D silicon?

If 3D silicon doesn’t come through, we’ll have to push more bits through copper.

3D silicon is nice because you can pack more into a smaller space.

3D silicon is multiple chips bonded together. Vias connect through the chips instead of traces.

The biggest delay for 3D silicon is that it turns on its head the entire value delivery system.

7 years ago, JEDEC started working on wide IO

What’s the difference between 3D silicon and having it all built right into the processor?

It’s the difference between working in two dimensions and three dimensions. If you go 3D, you can minimize footprint and connections

Flash memory, the big deal has been building multiple active layers.

The ability to stack would be useful for mobile.

Where is technology today with DDR?

DDR4 is now mainstream, and JEDEC started on DDR5 a year ago (2017)

Memory, DDR5+, and JEDEC – #24

“It’s a miracle it works at all.” In this electrical engineering podcast, we discuss the state of memory today and it’s inevitable march into the future.

Hosted by Daniel Bogdanoff and Mike Hoffman, EEs Talk Tech is a twice-monthly engineering podcast discussing tech trends and industry news from an electrical engineer’s perspective.

“It’s a miracle it works at all.” Not the most inspiring words from someone who helped define the latest DDR spec. But, that’s the the state of today’s memory systems. Closed eyes and mV voltage swings are the topic of today’s electrical engineering podcast. Daniel Bogdanoff (@Keysight_Daniel) and Mike Hoffman sit down with Perry Keller to talk about the state of memory today and it’s inevitable march into the future.


00:00 Today’s guest is Perry Keller, he works a lot with standards committees and making next generation technology happen.

00:50 Perry has been working with memory for 15 years.

1:10 He also did ASIC design, project management for software and hardware

Perry is on the JEDEC board of directors

JEDEC is one of the oldest standards body, maybe older than IEEE

1:50 JEDEC was established to create standards for semiconductors. This was an era when vacuum tubes were being replaced by solid state devices.

2:00 JEDEC started by working on instruction set standards

2:15 There are two main groups. A wide bandgap semiconductors group and a memory group.

3:00 Volatile memory vs. nonvolatile memory. An SSD is nonvolatile storage, like in a phone. But if you look at a DIMM in a PC that’s volatile.

3:40 Nonvolatile memory is everywhere, even in light bulbs.

4:00 Even a DRAM can hold its contents for quite some time. JEDEC had discussions about doing massive erases because spooks will try to recover data from it.

DRAM uses capacitors for storage, so the colder they are the longer they hold their charge.

4:45 DRAM is the last vestige of the classical wide single ended parallel bus. “It’s a miracle that it works at all.”

5:30 Perry showed a friend a GDDR5 bus and challenged him to get an eye on it and he couldn’t.

6:10 Even though DDR signals look awful, it depends on reliable data transfer. The timing and clocking is set up in a way to deal with all of the various factors.

7:00 DDR specifications continue to march forward. There’s always something going on in memory.

8:00 Perry got involved with JEDEC through a conversation with the board chairman.

8:35 When DDR started, 144 MT/s (megatransfers per second) was considered fast. But, DDR5 has and end of life goal of 6.5 GT/s on a 80+ bit wide single ended parallel bus.

9:05 What are the big drivers for memory technology? Power. Power is everything. LPDDR – low power DDR – is a big push right now.

9:30 if you look at the memory ecosystem, the big activity is in mobile. The server applications are becoming focused with the cloud, but the new technology and investment is mobile.

10:00 If you look at a DRAM, you can divide it into three major categories. Mainstream PC memory, low power memory, and GDDR. GDDR is graphics memory. The differences are in both power and cost.

For example, LPDDR is static designs. You can clock it down to DC, which you can’t do with normal DDR.

The first DDR was essentially TTL compatible. Now, we’re looking at 1.1V power supplies and voltage swings in the mV.

Semiconductor technology is driving the voltages down to a large degree.

11:45 DRAM and GDDR is a big deal for servers.

A company from China tried to get JEDEC to increase the operating temperature range of DRAMs by 10 C. They fire up one new coal fired power plant per week in China to meet growing demand. They found they could cut it down to only 3 per month with this change in temperature specs.

13:10 About 5 years ago, the industry realized that simply increasing I/O speeds wouldn’t help system performance that much because the core memory access time hasn’t changed in 15 years. The I/O rate has increased, but basically they do that by pulling more bits at once out of the core and shifting them out. The latency is what really hurts at a system level.

14:15 Development teams say that their entire budget for designing silicon is paid for out of smaller electric bills.

15:00 Wide bandgap semiconductors are happy running at very high temperatures. If these temperatures end up in the data centers, you’ll have to have moon suits to access the servers.

16:30 Perry says there’s more interesting stuff going on in the computing than he’s seen in his whole career.

The interface between different levels is not very smooth. The magic in a spin-up disk is in the cache-optimizing algorithms. That whole 8-level structure is being re-thought.

18:00 Von Neumann architectures are not constraining people any more.

18:10 Anything that happens architecturally in the computing world affects and is affected by memory.

22:10 When we move from packaged semiconductors to 3D silicon we will see the end of DDR. The first successful step is called high bandwidth memory, which is essentially a replacement for GDDR5.

23:00 To move to a new DDR spec, you basically have to double the burst size.

Intro to RF – EEs Talk Tech Electrical Engineering Podcast #21

Learn about RF designs, radio frequencies, RADAR, GPS, and RF terms you need to know in today’s electrical engineering podcast!

We sit down with Phil Gresock to talk about the basics of RF for “DC plebians.” Learn about RF designs, radio frequencies, RADAR, GPS, and RF terms you need to know in today’s electrical engineering podcast!



RF stands for radio frequency

00:40 Phil Gresock was an RF application engineer

1:15 Everything is time domain, but a lot of RF testing tools end up being frequency domain oriented

2:15 Think about radio, for example. A tall radio tower isn’t actually one big antenna!

3:50 Check out the FCC spectrum allocation chart

4:10 RF communication is useful when we want to communicate and it doesn’t make sense to run a cable to what we’re communicating to.

4:50 When you tune your radio to a frequency, you are tuning to a center frequency. The center frequency is then down converted into a range

6:30 Check out Mike’s blog on how signal modulation works:

7:00 Communication is just one use case. RADAR also is an RF application.

8:10 The principles between RF and DC or digital use models are very similar, but the words we use tend to be different.

Bandwidth for oscilloscopes means DC to a frequency, but for RF it means the analysis bandwidth around a center frequency

9:22 Cellular and FCC allocation chart will talk about different “channels.”

Channel in the RF world refers to frequency ranges, but in the DC domain it typically refers to a specific input.

10:25 Basic RF block diagram:

First, there’s an input from an FPGA or data creating device. Then, the signal gets mixed with a local oscillator (LO). That then connects to a transmission medium, like a fiber optic cable or through the air.

Cable TV is an RF signal that is cabled, not wireless.

Then, the transmitted signal connects to an RF downcoverter, which is basically another mixer, and that gets fed into a processing block.

13:50 Tesla created a remote control boat and pretended it was voice controlled.

15:30 Does the military arena influence consumer electronics, or does the consumer electronics industry influence military technology?

16:00 GPS is a great example of military tech moving to consumer electronics

17:00 IoT (internet of things) is also driving a lot of the technology

18:00 The ISM band is unregulated!

19:15 A router uses a regulated frequency and hops off the frequency when it’s being used for emergency communications

20:50 RADAR, how does it work?

22:22 To learn more about RF, check out App Note 150 here:




Wide Bandgap Semiconductors for Power Electronics – Electrical Engineering Podcast #20

Wide bandgap semiconductors, like Gallium Nitride (GaN) and Silicon Carbide (SiC) are shaping the future of power electronics by boosting power efficiency and reducing physical footprint. Server farms, alternative energy sources, and electrical grids will all be affected!

Wide bandgap semiconductors, like Gallium Nitride (GaN) and Silicon Carbide (SiC) are shaping the future of power electronics by boosting power efficiency and reducing physical footprint. Server farms, alternative energy sources, and electrical grids will all be affected! Mike Hoffman and Daniel Bogdanoff sit down with Kenny Johnson to discuss in today’s electrical engineering podcast.



Fact Sheet:

Fact Sheet

Tech Assessment (Good timeline information)

Agenda – Wide Bandgap Semiconductors

Use in Power Electronics

3:00 What is a wide bandgap semiconductor? GaN (Gallium Nitride) devices and SiC (Silicon Carbide) can switch on and off much faster than typical silicon power devices. Wide bandgap semiconductors also have better thermal conductivity. And, wide bandgap semiconductors have a significantly lower drain-source resistance (R-on).
For switch mode power supplies, the transistor switch time is the key source of inefficiency. So, switching faster makes things more efficient.

4:00 They will also reduce the size of power electronics.

6:30 Wide bandgap semiconductors have a very fast rise time, which can cause EMI and RFI problems. The high switching speed also means they can’t handle much parasitic inductance. So, today’s IC packaging technology isn’t ideal.

8:30 Wide bandgap semiconductors are enabling the smart grid. The smart grid essentially means that you only turning on things being used, and turning off power completely when they aren’t being used.

9:35 Wide bandgap semiconductors will probably be integrated into server farms before they are used in power grid distribution or in homes.

10:20 Google uses a lot of power. 2.3 TWh (terawatt hour)
NYT article:

It’s estimated Google has 900,000 servers, and that accounts for maybe 1% of the world’s servers.
So, they are willing to put in the investment to work out the details of this technology.

11:50 The US Department of Energy wants people to get an advanced degree in power electronics. Countries want to have technology leadership in this area.

13:00 Wide bandgap semiconductors are also very important for wind farms and other alternative forms of energy.

Having a solid switch mode power supply means that you don’t have to have extra capacity.

USA Dept of Energy: If industrial motor systems were wide bandgap semiconductors took over, it would save a ton of energy.

14:45 A huge percentage of the world’s power is consumed by electrical pumps.

16:20 Kenny’s oldest son works for a company that goes around and shows companies how to recover energy costs.

There aren’t many tools available for measuring wide bandgap semiconductor power electronics.

19:30 Utilities and servers are the two main industries that will initially adopt wide band gap semiconductors

20:35 When will this technology get implemented in the real world? There are parts available today, but it probably won’t be viable for roughly 2-5 years.

21:00 Devices with fast switching are beneficial, but have their own set of problems. The faster a devices switches, the more EMI and RFI you have to deal with.

Spread spectrum clocking is a technique used to pass EMI compliance.

24:00 Band gaps of different materials: Diamond 5.5 eV Gallium Nitride (GaN) 3.4 eV Silicon Carbide (SiC) 3.3 eV