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

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• 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 Shop 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 ZPUino developed by Alvaro Lopez. It allows you to slide in a range of peripherals.
  
• The ESP8266 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 LTC3330 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.
  
  
  
• 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:
  
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  • People with innovative ideas
    
  • A surplus of resources
    
  • An agency willing to invest surplus
    
  
  
  
• Where do new innovations come from?
  
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  • 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:
  
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  • 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.