Circuit Break - A MacroFab Podcast

• Parker
  • MAX6682 breakout board to read the thermistors
  • Engineer Spotlight on All About Circuits
  • Ford Climate Controlled Seat Module Breakdown 
    • Peltier setup
    • Temperature feedback is via thermistor 
      • 54K to 240K with the resistance around 170K at room temp
      • Possibly a NTC 200K?
    • Fan uses a LB11988HR from OnSemi 
      • 3 Wire
      • Interesting setup to control the speed of the fan
      • What part is Dpak with marking 065886A
• Stephen
  • The uTracer 3 design update 
    • Full on scope creep
    • Adding a STM32 mcu to control the relays to make it "safe"
• RFO
  • Digital circuits: Now with more analog!
    • Using memristors as data storage devices
    • Two memristors into the output totem-pole of a classic CMOS converter, between the usual p-mosfet and n-mosfet – effectively adding a potentiometer, whose wiper is the inverter output
    • Buy memristors?
  • Interviewing engineers? Should you bring your project or not?

Tags: All About Circuits, electronics podcast, Ford Climate Controlled Seat Module, LB11988HR, MacroFab, macrofab engineering podcast, MAX6682, memristors, MEP, Podcast, scope creep, Thermistors, uTracer

• Stephen
  • The uTracer 3 
    • A tube curve tracer that is very powerful.
    • Some upgrades that are in the mix 
      • New interface for selecting socket connections - going to have 8 and 9 pin sockets with rotary switches for each pin
      • Upgraded ground loop for measuring the grid current on triodes
      • Integrated FTDI
      • Transistor curve tracer (only tests the "positive" transistors PNP,N-Channel stuff)
    • Lab Notebook: http://dos4ever.com/uTracerNotebook/Notebook.html#Plate
  • SSPS - The entropy creator
• Parker
  • New Article: Key Parts of an Arduino: How to Integrate the Arduino Platform into your Product
  • Reading temperature NTC thermistors 
    • Voltage divider method
    • Wheatstone bridge circuit
    • Dedicated IC like the MAX6682MUA
    • Others ways?
  • Are space ships and space suits rated for external positive pressure? 
    • Relevant  Reddit Thread
• RFO
  • Saelig has a new programmable 128W Power Supply With 1mV/1mA Precision
    • Output: 0 – 16 Volts / 0-8 Amps
    • Resolution: 1 mV / 1 mA
    • Low Ripple & Noise: <= 350 uVrms / 3 mVpp / <2 mArms
    • Remote Voltage Sensing Capability
    • $260

Tags: electronics podcast, Key Parts of an Arduino, MacroFab, macrofab engineering podcast, MAX6682, MEP, Podcast, Saelig, SSPS, The Entropy Creator, Thermistors, uTracer, Wheatstone

• Brandon Satrom
  • Developer evangelist for Particle
  • The founder of Carrot Pants Press
  • Loves to talk about Javascript, open source, microcontrollers, robots, and what ever new shiny tool or technology that is currently distracting him
  • Kitchen Sink of badges designed for Maker Faire San Mateo.
  • Favorite Bagel
• Blinky of IoT
  • Parker unboxed a Particle Photon
  • Included in the box is a photoresistor, a LED, breadboard, and some resistors
  • Parker built the circuit and programmed the Photon in under 5 minutes
• Building an IoT Device
  • Spec Sensors 3SP Ethanol 1000
    • Low Power Consumption of around 10 to 50 uW
    • 0-1000ppm Ethanol range
    • It has 3 analog outputs 
      • Vgas which is proportional to the gas we are measuring
      • Vref which is around half the supply voltage and is used as a fixed zero reference
      • Vtemp is the temperature of the sensor used to set the temperature compensation
  • Particle Photon reading the analog outputs of the Spec Sensors 3SP Ethanol 1000
    • Posts to the cloud about the status of the sensors
    • Code for this can be found here
    • Issues porting the Arduino Code to the Particle Platform 
      • Floats -> Doubles
      • Particle.Variable do not show up if you are doing Particle.Publish too fast
  • The relay board is connected to an industrial light tower 
    • Light tower - NPTL5-W-E 
      • 24V
      • Pull down I/O lines to turn on lights
• Discount codes for MEP Listeners
  • Particle is giving MacroFab Engineering Podcast listeners a discount
  • Use the URL https://store.particle.io/discount/MacroFabFam to get 15% off anything in the Particle Store
  • For free shipping use the code “"ParticleFamShipping"
  • Gets a free starter kit with the mesh Particle boards by using the code "ParticleFamStarter"
• Announcements
  • Houston Hardware Happy Hour
    • June 7th at Slowpokes
    • Bring hacks and hang out

Tags: 3SP Ethanol 1000, BLinky of IoT, Brandon Satrom, Carrot Pants Press, electronics podcast, MacroFab, macrofab engineering podcast, MEP, Mesh Networking, Particle, Podcast, Serial Terminal, Spec Sensors

• Stephen
  • Mute circuit design
    • PDF of the schematic
    • Is it really digital or analog? What is the defining difference between the two
• Parker
  • Gameboy VGA project
    • Added SN74LVC8T245 level shifters
    • Designing a flat flex cable? 
      • Will document it on his blog
    • Left to do on the schematic side of things
      • VGA connector 
        • Possible L717HDEH15POL2 part?
      • 3.3V TTL -> Analog VGA signal 
        • Going to use a resistor ladder
        • Current dev board uses 4bit VGA with 500Ω, 1kΩ, 2kΩ, and 4kΩ ladder
      • Serial Terminal? Never have done this in verilog 
        • FT230X to USB
  • Brewery wiring
• R.F.O.
  • Summer projects ideas for senior in computer engineering
    • Car counting and just designing a PCB
  • SSPS update? :)
• Announcements
  • Twitter Chat Info 
    • May 25th Friday at 1PM CST
    • Use #MacroFab to join the conversation
  • MacroFab Monthly Electronics Meetup
    • May 23rd 6PM at MacroFab HQ in Houston
    • Brandon Satrom from Particle. Going to give a talk about IoT fundamentals.
    • We will stream it on Twitch for non-Houstonians
  • Houston Hardware Happy Hour
    • June 7th at Slowpokes
    • Bring hacks and hang out

Tags: electronics podcast, Flat Flex, Gameboy VGA, Is it really digital or analog?, L717HDEH15POL2, MacroFab, macrofab engineering podcast, MEP, Podcast, Serial Terminal, SN74LVC8T245, SSPS, Summer Projects

• Stephen
  • Moving to Denver, Colorado
  • Podcast will still go on in a remote form, similar to another popular electronics podcast
• Parker
  • Posted on his blog recently and will be doing more!
• R.F.O.
  • The Nintendo switch has been hacked – via hardware! 
    • First discovered by fail0verflow
    • Switch runs on the Nvidia Tegra X1 platform
    • Put the switch into a USB recovery mode by shorting out some pins on the Joy-Con Controller
    • Then trick the Switch's USB stack by sending a bad "length" argument
    • Allows homebrew and linux to run on the Switch
  • Say Hello to Android Things 1.0
    • Enables you to build and maintain Internet of Things devices at scale.
    • Provides hardware, rich dev api’s, and back end infrastructure
    • System-on-Modules (SoMs) - 3 year “long term support”
    • Raspberry Pi 3 Model B support for prototyping only
  • Listener email: "A topic I'd be interested in hearing you guys discuss is how you go about intentionally improving your engineering skills. I've been thinking a lot recently about the idea of achieving "mastery" of a skill and I'm quite interested in other people's take on the topic."
• Announcements
  • Twitter Chat Info 
    • May 18th Friday at 1PM CST
    • Use #MacroFab to join the conversation
  • MacroFab Monthly Electronics Meetup
    • May 23rd 6PM at MacroFab HQ in Houston
    • Brandon Satrom from Particle. Going to give a talk about IoT fundamentals.
  • Houston Hardware Happy Hour
    • June 7th at Slowpokes
    • Bring hacks and hang out

Tags: electronics podcast, MacroFab, macrofab engineering podcast, MEP, Podcast

• Mashup episode with Embedded.FM
  • Elecia White and Christopher White are the hosts of the Embedded.FM podcast 
    • It is a podcast dedicated to the many aspects of engineering
    • Elecia and Christopher talk about the how, why, and what of engineering, usually devices
    • The focus is bringing on guests and experts onto the podcast
  • How to make Software and Hardware Engineers work better together
  • Schematics for the Apollo Guidance Computer and their Kicad replica on github
• Announcements
  • Twitter Chat Info 
    • May 11th Friday at 1PM CST
  • MacroFab Monthly Electronics Meetup
    • May 23rd 6PM at MacroFab HQ in Houston
    • Brandon Satrom from Particle. Going to give a talk about IoT fundamentals.
  • Houston Hardware Happy Hour 
    • June 7th at Slowpokes
    • Bring hacks and hang out

Tags: Christopher, Elecia, electronics podcast, Embedded.FM, firmware, MacroFab, macrofab engineering podcast, MEP, Podcast, Software Engineers

• Stephen
  • Fixing Jerry's Amp that picks up radio signals
  • The Johnson Noise
  • E34L Tubes
• Parker
  • DAC Article Part 3 Complete
  • DAC fixture parts arrived to finish Part 4 of the article series
  • Details on the MacroFab plans for DefCon 26
  • Gameboy Update 
    • Check out the youtube video from the BenHeck Show
  • Tried out the new Eagle V9
  • PinHeck update on the software side
• RFO
  • PCB Grounding 
    • Star Grounds
    • Plane and Plunge
    • Galactic Grounding
    • Analog devices article on grounding
  • Tiny Arduino + FPGA = Sno
    • Altera MAX10 based development board
    • The MAX10 comes preprogrammed with functions that match the Arduino API
    • These built in modules do the analog to digital conversion, servo control, operate NeoPixels, and a host of other functions
    • HackaDay Article by Al Williams who has been on two previous podcasts: EP#57 and EP#94.
  • Analog-rich MCU shoots for sensor nodes
    • Microchip PIC16F18446
    • ADC can run with the processing core shut-down, waking the core when required
    • You can sign up for a free board here on the Microchip site?
    • MPLAB Xpress PIC16F18446 Evaluation Board

Tags: DAC Article, DefCon26, E34L Tubes, Eagle V9, electronics podcast, Johnson Noise, MacroFab, macrofab engineering podcast, MEP, PCB Grounding, PIC16F18446, PinHeck, Podcast, Sno FPGA

• Trey German
  • First guest on the MEP way back on EP#10
  • Second appearance was EP#38
  • Icarus Trophy
  • Polymorphic Labs
  • Stewart & Stevenson M1083
• Announcements
  • Twitter Chat Info 
    • April 27th Friday at 1PM CST
  • MacroFab Monthly Electronics Meetup
    • May 23rd 6PM at MacroFab HQ in Houston
    • Brandon Satrom from Particle. Going to give a talk about IoT fundamentals.
  • Houston Hardware Happy Hour
    • May 3rd at Slowpokes
    • Bring hacks and hang out

Tags: electronics podcast, Icarus Trophy, M1085, MacroFab, macrofab engineering podcast, MEP, Podcast, Polymorphic Labs, Trey German

• Stephen
  • Using an oscilloscope as a dynamic signal analyzer
  • Analog scopes
• Parker
  • Gameboy update 
    • Code compiles! Quartus II still compiled my Gameboy Project
    • 1.25mm? pitch 21 pin. Connectors are hard to find.
    • Custom flexi cable to solve the problem?
    • Should have board laid out next week
  • Arduino Article
    • Raspberry pi addon boards are called HATs - Hardware attached on top
    • Missed opportunity for calling them pi plates :(
• RFO
  • Fatberg follow up
    • First mentioned on MEP EP#85 Space Engineers VS Caffeinated Chipmunks
  • QHL600/750 Series DC-DC Brick Converters by XP Power
    • 600 W or 750 W and are designed for 300 VDC nominal input applications
    • 180V to 425V DC input
    • 4.60" x 2.40" x 0.50"
    • Ideal for AC input applications with PFC, baseplate cooled ESG solutions and high voltage battery applications such as electric vehicles
  • Found a 300V capacitor repackaged as 450V
    • How to test the voltage rating on caps?
  • Have listeners ever purchased counterfeit or fake parts? Let us know!
• Announcements
  • Twitter Chat Info 
    • April 20th Friday at 1PM CST
  • Meetup Info 
    • May 23rd 6PM at MacroFab HQ in Houston
    • Brandon Satrom from Particle. Going to give a talk about IoT fundamentals.
  • Houston Hardware Happy Hour 
    • First Thursday of each month
    • May 3rd at Slowpokes
    • Bring hacks and hang out

Tags: Counterfeit Parts, electronics podcast, Fake News Parts, Fatberg, Gameboy VGA Adapter, HAT, MacroFab, macrofab engineering podcast, MEP, Pi Plates, Podcast, QHL600, QHL750

• Stephen
  • LM13700
    • Dual Operational Transconductance Amplifiers With Linearizing Diodes and Buffers built by Ti?
  • All passive filter
    • Not just a zero ohm resistor ;)
    • Shift the phase
  • Fixing a Kegerator 
    • Kegerator was out of gas
    • R-134A
• Parker
  • USB Type C article? Updating old USB 2.0 from MicroUSB to Type C?
  • Going to finish my Gameboy VGA adapter 
    • Move to HDMI afterwards?
    • BenHeck Show Giant Game boy runs an early version of the code
• RFO
  • Amazon’s in-home delivery service now supports eight smart locks 
    • Help avoid porch pirates
  • FTC says “Warranty void if sticker removed” is not valid
    • Companies can't put repair restrictions on their products unless they provide the parts or services for free or receive a waiver from the FTC.
    • regulation for right to repair, is more about the posibility for getting the spareparts, and maybe cutting down on electronics waste.
  • Avoiding side entry to SMT pads?
• Announcements
  • Twitter Chat Info 
    • April 13th Friday at 1PM CST
  • Meetup Info 
    • Parker will discuss Key Parts of an Arduino
    • Trey German will talk about taking off-shelf enclosures and customizing them. Shout out to @yertnamreg 
      • MEP EP#10 and MEP EP#38
  • Houston Hardware Happy Hour 
    • First Thursday of each month
    • May 3rd at Slowpokes
    • Bring hacks and hang out

Tags: All-Pass Filter, Amazon in home delivery, electronics podcast, FTC, Gameboy VGA Adapter, Knowledge Base, LM13700, MacroFab, macrofab engineering podcast, MEP, Podcast, R-134A, SMT Pads, Thermal twisting, USB Type-C, warranty void stickers