The Amp Hour

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"Impedance Matching" with Davidson and Vandenbout - Presbytes Pushing Portfolios Jan 15, 2015

Show notes

Welcome Bob Davidson of Ambient Sensors and Dave Vandenbout of XESS corporation!

Bob has been developing products, including a new project that will only fit one way in a project box.
A software asked about building hardware and why it wasn't as "errorless" as how they build a skyscraper. Chris mentioned that the Peter B Lewis building at CWRU has a design flaw...it dumps snow on kids walking by.
Dave says Harrelson Hall at NC State is circular so the classrooms are wedge shaped.
This episode was inspired by a Twitter conversation between Bob and Dave talking about S hop Class As Soul Craft.
Bob used to work at HP. Dave used to work at Bell Labs.
At Bell Labs they tried doing too much vertical integration...instead of being allowed to effortlessly design in a 6801 2K rom...the internal chip design group wanted them to use the Mac4 microcontroller.
Dave (who owns/runs XESS) has been working in the ZPU ino developed by Alvaro Lopez. It allows you to slide in a range of peripherals.
The ESP 8266 is a simple wifi model (with dubious CE certs). Costs $2.70, has an LX170 from Tensilica. However, it's not low power, it uses 100 mA in transmit. Dave wrote about the ESP8266 here.
Bob has been working on a sensor array for a grape vineyard. It is networked in a hub and spoke model. It has energy harvesting using the the LT C3330 and solar cells.
The project stores energy in industrial batteries, the Tadiran TL4935 (about $8 each).
Both Bob and Dave used to be university professors but stopped because the focus is on grant writing and not building things.
Dave says that he is looking for all Fs and one A...because that means they're invested in that one thing.
Furthermore, the university only rewards one way of success.
Dave says, "I'll renounce cynicism when it ceases having predictive powers"
When asked about how young engineers can excel, both list ham radio and developing embedded hardware as ways to get ahead. Mostly building up a portfolio of projects.
When a project was cancelled at Bell Labs (often), Dave and a co-worker would sing a song that sounded like the Johnny Carson (tonight show) theme song. https://www.youtube.com/watch?v=keiuXB3dJ0E
Bob says that they used to have "Next bench syndrome", solving a problem for an internal customers.
Patents cost $10K to get it, $100K to defend it the first time
Management by wandering around.
Dave mentioned a book by Quigley about civilization. It takes three things:
- People with innovative ideas
- A surplus of resources
- An agency willing to invest surplus
Where do new innovations come from?
- Dave says, "What's close to what?"
- Bob says, "find problems that people have"
Bob developed an award winning system for how hard football players get hit and whether they have concussions. But it was not a guaranteed commercial success.
When it comes to quickly iterating hw, Bob brought up our interview with Erie Ries.
Lean Hardware is possible, it's all about how much you're willing to pay.
Bob uses both OSHpark and Sunstone for quick turn PCBs.
For CMs, Bob uses Western Electronics and Computrol.
Saleae recently wrote about their issues with costs and doing in-house manufacturing (specifically by buying a PnP machine). Bob has a Pro16 and says they are doing things right.
Bob was a co-author on "Getting started with bluetooth low energy" book. It was written in less than 6 months in order to be ready by SolidCon (where Chris met Bob in person).
The co-authors were:
- Kevin Townsend (@microbuilder)
- Akiba (@freaklabs)
- Carles Cufí in Barcelona, who is also an employee of Nordic Semi.
When teaching the main rule is: You have to keep one chapter ahead of the students.

Many thanks to Bob and Dave for returning to the show! To hear their first appearances, check out Bob in Episode 144 of The Amp Hour and Dave in episode 181. Both were great discussions about their pasts.

Supply Chain Woes And Wares - Nonplussed Neotechnic Nithing Jan 08, 2015

Show notes

Dave and Chris recall minimum wage not so fondly, except having cash in hand.
Dave has been having trouble getting his Maxim parts in hand, but it was actually DHL getting them stuck in customs.
When working with small quantities, ordering parts up front can be a necessity. @Roteno tweeted about doing a design and getting stuck without any stock in the world.
Bunnie Huang (former guest) writes about the 'soylent supply chain' ("It's made of people!"). Much of business is still done based upon relationships and working with other humans.
Distributors have changed and consolidated, even since when Chris started working in the industry. Dave's friend used to collect and compare business cards so he could see as sales people jumped from one distributor to another.
FAEs aren't likely to go away any time soon, nor will factory applications engineers. Marketing rep firms might though. Chris explained the difference between types of sales/marketing/technical support engineers on Engineer Blogs back in the day.
Dave now has an article on wikipedia! Quick, someone deface it!
Elon Musk recently did a fantastic AMA on reddit. This made Chris realize he doesn't really care about space (electronics); more specifically rockets seem boring, but it's likely ignorance about the required specs for doing something like that (similar for a Model S).
The Hardware Battlefield showcases new hwstartups at CES, a range of which don't seem to be doing interesting tech. This competition feels similar to D ragon Den/Shark Tank.
Chris mentioned the a lot of hwstartups aren't that interesting because of the fields they cover, but one that has been interesting (though it's "older" now) is Boosted Boards. Here's a good review of them:

https://www.youtube.com/watch?v=v8hFcDhBgZ8

Amazon has big changes coming to Lab126 (designers of the Kindle) after failures of the Fire Phone. This highlights how even in big companies, even the "research" departments aren't immune to the sales cycle (which may point to the fact that they aren't truly research at all).
Dave used to do research by doing long term testing of components. This still isn't basic physics/academic research, but it's closer than the development Chris mostly did.
Bell Labs was able to operate because of the margins MaBell had due to their monopoly. Much like modern distributors, these margins continue to shrink.
Graphene seems like a physics experiment that is on the cusp of being useful for the past 5 years. The New Yorker has an interesting piece comparing the graphene timeline to that of aluminum, which took nearly 50 years for its first commercial use and another 50 for its widespread use.
The student who was told "No Microcontrollers" had a clever workaround.
iRobot is offering the hackable Roomba for $200. Former guest Scott Miller used to run manufacturing for them.
Dave is moving onto the next round of hiring for his intern. Still no word on which CAD package they'll use, though many Aussie students learn Altium because it's given to the Universities there to get them hooked.
Chris is excited about the upcoming (but not research-new) feature on KiCad: Matched impedance calculation for traces as their being drawn.
While Chris was interviewing after leaving college, he took part in a group interview.
Will the changes to how courses are delivered to students affect how they learn and are hired for jobs? Do courses like this Georgia Tech online course help students stand out? Veritasium did a video about how online courses won't revolutionize education, just like technologies before it.

https://www.youtube.com/watch?v=GEmuEWjHr5c

Prepping For Hoverboards - Gallionic GitHub Gabble Dec 31, 2014

Show notes

Dave is mentally preparing himself for buying a hoverboard. Getting one of those is more likely than being able to go out NYE when you have a kid.
In Austin, the Alamo Draft House is showing a 20 hour marathon of Hobbit and LOTR movies (with food).
Dave has been having issues rendering high frame rate videos.
The 80386 also used the 80387 Math co-processor. This was required for some CAD programs. Other ones like Protel came with Hercules mode (using the expensive Hercules video card)
Chris will be demoing during a trade show in January (DesignCon)
Contextual Electronics will be starting up again January 19th. The format has changed in order to match reality, with more iterative design and with less linear paths to learning.
Chris also made a video detailing things that are good to check out before starting CE:" https://www.youtube.com/watch?v=obKwQXlr_b4
Writing (or planning) your firmware up front can help you make hardware decisions. Dave did this for the uCalc watch because it was a design contest entry.
The Gantt chart is a ridiculous tool of managers, yet we have all had to deal with it.
Chris was recently on The Engineering Commons (his old podcast) once again, discussing how much of design has moved onto silicon. He said it could be irresponsible to design with discrete parts because the low cost and better specs of some newer parts so far outstrip most discrete solutions.
Dave talked about a similar situation (designing a VGA to HDMI conveter) on a mailbag video recently: https://www.youtube.com/watch?v=CQgJmmn-eSE
Chris referenced Jim William's app note (AN28) about temperature measurement...a classic! LT has a recent product that blows some of those specs out of the water though! The LTC2983 is pricey but looks awesome.
LT jumped on the bandwagon and now offers Arduino sketches to exercise chips. They have a derivative platform called the Linduino.
Dave has a t-shirt idea: It's 2015: Instead of hoverboards, we got was the Arduino.
Chris was intrigued by a question posed on /r/ECE: What are some important topics that aren't taught in EE/CE school?
Dave still hasn't tried out Git/GitHub. Chris recommends running from the command line and explains why the repos online look so confusing.
Chris recommends at least using Dropbox for revision control. You can go in and find older versions of files.
Altium has a version control system build on top of Subversion (SVN). It's really meant for collaborative design (which Dave and Chris don't think is necessary unless you're a huge company).
If you want a friendly way to view Git repos, check out SourceTree from Atlassian. It helps to visualize revisions/branches/merges/etc.
Dave had to deal with a lot of this stuff when his Makerbot was bricked.
When Dave finally hires an intern next year, he'll have to decide which PCB package he'll purchase/use with them. Altium is planning to release a mid range version called CircuitStudio alongside CircuitMaker. Chris still picks KiCad, which Dave says is a possibility. Chris didn't like going back to EAGLE after all these years.
Dave released an eevBLAB video about spelling errors. It's really more about how you present yourself than how many typos you might have. https://www.youtube.com/watch?v=h2sOEN_TVT4
There are tons of great videos that have been posted from Chaos Communication Congress. Check out some great talks (among many more!):
- Towards General Purpose Reconfigurable Computing on Novena (Starts around 18:00)
- An Open Hardware and Software Platform, Based on the (nominally) Closed-Source MT6260 SoC
Thanks to everyone who made 2014 great! Also thanks to Paul Stevenson for donating The Amp Hour theme! We still love it!

MightyHohm For The Holidays - Kaiser Keyzer's Kits Dec 25, 2014

Show notes

We are joined once again by our old friend Jeff Keyzer (Mightyohm)!

Last time Jeff was on show was after the 2013 Open Hardware Summit (episode 162).
Jeff has been working on a new high volume consumer product and has been experiencing the need for DfX. Instead Jeff has learned that shotgunning issues is a more likely way to find problems.
Back in the day Jeff used to do III-V semiconductor PA design. This was part of what we talked about last week with Shahriar.
Dave was very curious about whether Valve would be showing anything at the upcoming CES.
Dave just tore down an Apple Lisa: https://www.youtube.com/watch?v=_hxdz6c8bHg
Chris asked if Dave and Jeff have needed to use IEEE 488/GPIB/HPIB for programming test equipment.
Jeff (and his wife) have still been selling the Geiger Counter kit, both online and through distributors like adafruit.
Adafruit has a tutorial about packing and shipping kits and talks about using a c ounting scale.
Dave is currently hiring an assistant, but didn't expect people to apply from outside the country. They would need a travel visa to work with Dave. https://www.youtube.com/watch?v=9_qhlFc-MVU
Jeff hasn't found too many in-person hardware events in Seattle but the Kent mic and key swap meet has been well maintained and interesting. Jeff compared this to the De Anza swap meet down in Silicon Valley.
Jeff got to see Mike Ossmann speak (from afar) at TAPR. Microsoft has a HAM group called microhams.
One of the most north-westernly conferences in the US is ToorCon.
Jeff also wants to visit the Hanford Superfund site/reactor in eastern Washington where they enriched some of the early plutonium for US projects.
There is a Living Computer History museum in Seattle paid for by Paul Allen.
Another museum (the Space Gallery) is owned by Charles Symonyi. He was the lead developer of Micosoft office; Bill Gates hired him because he did a phd on compiler design.
The 1405 intel chip was recently decapped and photographed by Ken Sheriff.
Jeff has thought about making an art project out of scope he picked up at swap meets. like the ICO435.
What Jeff really wants is the Keysight MSO4000 series. He likes things like the touchscreen and the USB analyzer.
Another piece of test equipment that would enable a lower cost RF consultant would be a piece of equipment like the Fieldfox.
Jeff has found a bunch of low cost/no cost tools for RF design:
- LT Spice
- QUCS (outputs S2P files)
- AppCad
- NEC antenna sim, EZNEC
The Art Clock was an impressive project that Dave posted about recently.
Adafruit has an article investigating who owns and the history of Heathkit (and an update today).

An Interview with Shahriar from The Signal Path - Quisquous Quivering Quadripole Dec 18, 2014

Show notes

Welcome Shahriar from The Signal Path! If you’re not already, you should definitely be subscribed to the YouTube channel.

Shahriar currently works in the ASIC design lab that is part of the Murray Hill building at Bell Labs.
The millimeter wave researchers often say "GHz is basically DC"
Making higher speed complex devices can be difficult but there was a 2006 paper that had a 81Gb/s timer.
ST Micro has one of the leading SiGe BiCMOS high speed.
The ASIC group has some of their research work fabricated at TowerJazz because it is approved by the government.
The government has been focused on III/V semiconductor technology - InP and GaAs, GaN
The PA/front end of cellphones/wifi uses GaAs (instead of Si) because of breakdowns of submicron processes.
Chip designers get design kit from the fab and these are used in simulations. Here is an example of one from TSMC, provided by MOSIS (discussed previously on the show)
Shahriar usually tests new design kits with a LNA/PA. He also designed a 160 GHZ PLL as a student.
3 um x 3 um capacitor is 12 fF.
The ASIC designers use 3D EM simulation from Cadence.
Design kits will have variations: DC characteristics like transconductance (gm) might be ok but the designers know the capacitance will have uncertainty as they characterize the design kit more.
Dave recently did an EEVblab about what a hobbyist should know. Shahriar agrees and things knowing to test is very important. https://www.youtube.com/watch?v=9iXFhKUa1BU
Chris loved Shahriar's cryo experiments because they really showed the (extreme) effect of temperature on components. https://www.youtube.com/watch?v=MpCQsB1VK24
Testings for THz can require complex/custom test gear. Often it is a network analyzer with a front end. OML, VDI make extenders for Anritsu, Keysight.
One Signal Path episode used a Keysight/Agilent 62GHz oscilloscope, it was on loan from the dealer. https://www.youtube.com/watch?v=dx596o8t_TY
On scopes you start to run into the noise floor of the ADC (b/c jitter). This limits around 100 GHz. At 110GHZ the connectors become limiting (1 mm). If the connectors go to .8 mm, it could go up to 160 GHz.
Shahriar has a range of research papers: http://scholar.google.com/citations?view_op=new_group&hl=en&nun=Shahramian&imq=author:%22Shahramian%22&authorid=2011075341937338871
Peer review is critical for journals. Bell Labs splits research between keeping it private and publishing it.
There are a range of technical conferences for millimeter wave research: ISCCC, SiRF, SSYCs, IMS conference
A phased array is a grid of antennas. It allows steering the signals towards the source/receiver.
Different high GHz bands are great because of the open bandwidth.

Space Bound, Again - Xtreme Xtraplanetary Xenonosocomiophobia Dec 11, 2014

Show notes

Dave has secured his new basement/garage space! The EEVbunker! https://www.youtube.com/watch?v=aeCyhWSPqfc
Dave was once working (from home) on Christmas Eve to try and get stuff ready for CES
Some of our favorite video bloggers:
There is another SF meetup that Chris will be at. This one will feature Shaun Meehan from Planet labs and someone from the Javascript based processor called Tessel.
Dave recently completed the mud run in Sydney. He also did a teardown of the scope he took with him. https://www.youtube.com/watch?v=VZCokbsTwmQ
Chris and Dave had both had to deal with extended life testing (Thermal/humidity testing). One possible solution is c onformal coating.
Australian alarm company Hess designed in MOVs for thunderstorms...but didn't populate them for non-monsoon-colocated systems.
Fixing scopes isn't for the faint of heart. Sure, pros like Jim Williams and Kent Lundberg (former guest) fix them up for fun, but you could be signing up to jump down a rabbit hole.
Dave recently fixed his BTTF time circuit
The Orion launch/landing were a spectacular set of videos. Also NASA officially announced going to Mars! https://www.youtube.com/watch?v=UEuOpxOrA_0
Aldrin's book (and concept) about building our way to Mars vs the Mars direct (described in a book by Robert Zubrin)
Apollo 8 was impressive to Dave because it was not only a manned mission...they also decided to "go for it" and get around the moon.
Dave lamented Maxim's delivery. There was an interesting post from a Maxim insider about the priorities at the company (that match what we expected).

An Interview with Colin Karpfinger - Blendling Bean Brio Dec 04, 2014

Show notes

Welcome, Colin Karpfinger of Punch Through Design!

Colin is from Milwaukee (woot, midwest). He went to school in Minneapolis and started his consulting company there. There is still a PunchThrough office there.
Their first official product was the LightBlue app, a development application on the iPhone.
The first hardware product was the Light Blue Bean, a bluetooth communicating, Arduino compatible development board. It costs about $26-$30 per unit.
The Light Blue Bean integrates their other hardware product, the LBM313 module. These cost about $8 per module.
They had to go through FCC cert. Also IC, CE, MIC, KCC.
The general costs to get certified was $40K and 2-3 months.
There is also a board that helps to breakout and test the Light Blue Bean, the Vegas Lounge
PunchThrough rolled their own crowdfunding solution when launching the bean (no longer available but you can view their backer updates on their blog). They also ticked the price up each day. This resulted in pre-selling over 9000 units.
Apple salts the BT id for security.
The Light Blue Bean was manufactured in Korea and delivered via a fulfillment service.
The testing of the beans was gamified for the manufacturing staff. They showed some of these on their Vimeo site. LightBlue Bean Test Jig from Punch Through on Vimeo.
The LBM313 uses 0201 parts and has square pads under the module. This can be soldered directly to another PCB. The Light Blue Bean is only a 2 layer board.
The modules uses the CC2540 chipset from TI.
The latency is one of the limiting factors. The Miselu (iPad keyboard launched on kickstarter) needed to control for this.
Another music based product, the Retronyms Wej is another music based product. It is a tabletop, open source MIDI unit.
So why Apple support to start with? It's the Bluetooth stack. Apple added non-approved features and now they are getting pushed back into the bluetooth standard.
These relate to the central and peripheral roles - sensor is usually peripheral, phone is usually the central. The iPhone can be both.
The LightBlue app can simulate hardware. This is probably why FitBit recommended it as the "Find my hardware" app of choice.
There is now an Android SDK for BTLE. The Windows based development tools are also coming.
Now it is possible to run your Light Blue Bean apps from an iPhone or iPad. Interestingly, the compiler isn't on the iPhone/iPad app, it's on the cloud (and can also sync sketches with your Dropbox).
Punch Through is hiring! Send a resume and portfolio of projects to info at punchthrough dot com.
They are also giving away beans to the top 10 holiday bean usage ideas!

You can follow Colin or Punch Through on Twitter. Many thanks to Colin for being on the show and telling us about balancing product design and consulting and the Light Blue Bean! Be sure to pick one up for yourself and try it out today!

Worktrips and Workspaces - Junket Jactation Jiltedness Nov 27, 2014

Show notes

Chris is back from his European adventure and Dave is buying a new space!

Chris was at Electronica in Munich two weeks ago.
The winner of the Hackaday Prize was announced at an event on the Thursday of that week. SatNOGS won the grand prize (a trip to space).
Dave was up on the big screen because he announced his judging winners https://www.youtube.com/watch?v=mFAVUcrltpg
There are also videos for each prize entry: SatNOGS, RamanPi, PortableSDR, ChipWhisperer, Open Source Tricorder.
The last day the show is a bit more deserted (compared to above).
An example booth size from Maxim.
Dave is buying a new space (hopefully). It will be a storage/workshop space.
Chris met the people making the RasPi CommPlus who are from Austria (not Australia). It is in an interesting hard spot between industrial hardware, medium price and a crowded marketplace.
The Mu Thermal team has finally said they will not be meeting their production target. Companies like Seek and Flir are doing sensor innovation, whereas Mu was dependent upon 3rd party sensor tech.
The Planet Labs team is putting up their next set of "Doves" on a SpaceX rocket. Shaun was on the show previously and will be speaking at a TBA event in SF.
The site that Chris has been working on (Parts.io) is now open to the public.
Dave found a cache of popular electronics PDFs.
We now have a Patreon account! Please support the show if you can.

Next week on the show we will have Colin Karpfinger from Punch Through Design (makers of the Light Blue Bean). Happy Thanksgiving to all US listeners!

Meracious Mike Manuduction Nov 12, 2014

Show notes

In this technical action packed show while Chris is away at the Electronica show in Germany, Dave & Mike Harrison from Mikes Electric Stuff discuss project design, manufacturing, quick turn PCB and project design, DIY stencils with the Silhouette Cameo vinyl cutter, $300 pick and place machine viability, parts procurement, large LED system design, LED diffusing and gamma correction techniques, and trade action stories.

And are Mouser breaching customer confidentiality?

Space Difficulties and Lost Heroes - Wanzing Workshop Whemmle Nov 06, 2014

Show notes

Chris will be at the Hackaday Munich event where the winners of The Hackaday Prize will be announced.
Chris and Dave think of Dieter's Dream and European Vacation when they think of Germany, a far cry from reality.
The Woz announced he will be teaching at a University in Australia, no word if he'll end up living there.
The reason for Chris' Germany trip is Electronica. It will be huge.
Dave has been to CeBIT before, a large conference and show in Australia.
Is the role of conferences declining? Specialized knowledge can be found online, so there is less incentive to be at an inperson event.
Tom from Car Talk recently passed away. He was an inspiration to our show, not least of all for showing that programs with two weirdos laughing their butts off can succeed.
One of our listeners put together a clip just from us laughing during a show: https://www.youtube.com/watch?v=dESWV27chqs
uBeam is back in the news for getting $10M and for an explaination from a physicist on why it won't work (and why investors are dumb).
The show Silicon Valley is relatively accurate, even if it is ridiculous.
The noted "Father of the LED" was wondering why he didn't get a Physics Noble prize. The three inventors of the blue LED recently were awarded the Nobel.
A list of Physics Nobel prizes shows that only recently have any electronics prizes been awarded.
There is a new ultrasound chip, being worked on by our recurring guest Greg Charvat! He mentioned when he was on last time that he couldn't talk about what he was working on...but it's this!
Greg will be at an expert panel event in NYC, hosted by the parent company of the startup he is at.
Researched recently proved that DNA can carry current, paving the way for self assembling circuits.
Chris dressed up as "Tony Stark at a cocktail party" for Halloween. Dave hates Halloween.

https://twitter.com/Chris_Gammell/status/528730939388870656

This provided a good excuse to break out the mill for the plastic case and to attempt milling a circuit board.
The pcb2gcode script helped for generating gcode from gerbers. Chris broke all of his milling bits and ended up hacking something together.
There is also a script that will turn a 2D vinyl cutter into a solder stencil cutter. Thanks to Jeremy for letting us know about it in the comments two weeks ago.
Inventables is running a kickstarter for a "2.5 carving machine" called Carvey. It's really a low height milling machine but their online CAM tool Easel looks neat as well!
There is another Kickstarter for a reflow oven controller, however it also has kit elements to build it up. They have a great tutorial for building your own.
Mike did a teardown of the Seek Thermal camera, showing how simple the guts are. Chris got one as well, but it's his first thermal camera so he didn't notice the difference. https://www.youtube.com/watch?v=8Cr8oZck5m8
The USB On-The-Go (USB OTG) being used on the Seek could end up enabling a new generation of higher bandwidth hardware with associated apps.
There is a Hoverboard on Kickstarter (that works!) but man is it loud and not very practical. Buzz Aldrin came in to try it out, Dave is wondering why he wore a helmet.
We were sad to see the Antares rocket explosion. We were glad no one was hurt though.
We were even more sad to see the crash of Space Ship Two, where the pilot died.
Recent former guest of the show Shaun Meehan talked about the "doves" deployed with his co-workers at Planet Labs. 26 of them were lost on the Antares explosion.
Dave wondered if there is such a thing as satellite insurance. There is. Quite a bit actually.
Dave posted an eBook about Global Certifications, aimed at makers taking their projects pro.
We will give away a code for a copy of this eBook to the first 5 listeners to tweet:
- A link to this show
- @TheAmpHour (include our name in the tweet so we know you tweeted it)
- And the hashtag #eBook

The next two weeks will be Dave and guests! Chris will be in Germany and Austria traveling and talking electronics with Europeans.

Thank you to Stuart Rankin for the picture of the “Catastrophic Anomaly”

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