MEP EP#30: You won’t believe this ONE¬†WEIRD Engineering trick.

Parker Dillmann |   |  Bots, clickbait, Engineering Podcast, IoT, MEP, Podcast, SAIM, Selective Solder, SSPS

MacroFab Engineering Podcast


Download: MP3
RSS Feed: Link

Runtime: (34:41)

Parker Dillmann
Stephen Kraig


Stephen working on the SSPS

Figure 1: Stephen working on the SSPS. Trying to figure out why the transistors are getting hot with no load.
Engineering Clickbait
Figure 2: Engineering clickbait headlines (if they existed).

Podcast Notes

  • Parker is working on streamlining the Selective Solder Process at MacroFab. Writing a script that will take XYRS data and generate the G-Code for the machine.
  • Design work on a calibration board for visual systems like the SAIM and calibrating the Selective Solder is being designed.
  • Stephen is getting the analog side of the SSPS working. The -35V rail has a blown transistor. He found that pnp transistors were flipped C to E!
  • After testing the circuit node by node, Stephen found some deviations from the simulation. The feedback voltage was supposed to be about 34 volts but it was reading 15.2 and -1.78 for both regulators. Put the scope on the fb nodes and found that the + error amp was oscillating at 12.6kHz and the – regulator was at 2.4kHz. Both error amps has insufficient control feedback. Added a 1M resistor with a 100uF cap in parallel and the oscillation went away (See Figure 1).
  • Engineering click bait article titles. Parker came up with “5 Cost Saving Tips No Contract Manufacturer Wants You to Know About”. Stephen has “The PCB went in the oven. You will never guess what happens next”.
  • Parker wants to design a small battlebot type platform that utilizes an entire 16″x16″ panel that includes the mechanical chassis parts. Can reuse the controller board for even larger bots.
  • Popular Internet of Things forecast of 50 billion devices by 2020 is outdated. Revised to 30 or so Billion depending on who you talk to.

Special thanks to whixr over at Tymkrs for the intro and outro theme!