MacroFab Engineering Podcast

MacroFab's Engineering Podcast! Where Electrical Engineers, Parker Dillmann and Stephen Kraig talk about electrical engineering topics, DIY projects, and industry news. Sometimes cool people stop by the podcast to drop some knowledge.


episode 237: Ice Cream Solder Paste Equipotential

MEP EP#237: Ice Cream Solder Paste Equipotential

  • Cat Feeder Unreminder
    • Started designing the parts and symbols in Eagle.
    • Will post more on twitter as I build the components and put together the symbols
  • Garage Door opener hacking
    • Converting my normal style garage door opener to a “jackshaft” style opener
    • Why?
    • LiftMaster, Chamberlain, Craftsmen are all the same
    • Mine is a Liftmaster Formula 1
      • Belt drive need to convert to chain drive to attach to the jackshaft
      • All of these use similar drive mechs
    • Other things that are needed
      • Garage door auto lock
        • SureLock Garage Door DeadBolt
      • Cable tension switch
        • LiftMaster 41A6104
  • High voltage low current measurement
    • Resistive dividers?
      • Caddock 1776-C681
      • 10M ohm
      • 0.1% tolerance with 0.05% matching
      • Low PPM
      • This method is ok but requires a rather large current sense resistor which is not great.
    • Floating supplies
      • This is how multimeters work. The reference is floating.
    • Isolation solution
      • May go with an isolated solution - basically a power supply that isolates the secondary.
      • Isolated digital communication down to LV side.
  • Tests for pcb shielding
    • Did a shield plane test on a new pcb assembly.
    • Top and bottom pours that respect clearance rules.
    • 5mm pitch via stitching.
    • All terminate to one pin on a 2 pin header.
      • Second pin connects to a plated bolt hole that goes to chassis.


 2020-08-13  57m