Description

MEP EP#237: Ice Cream Solder Paste Equipotential

Parker

• 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

Stephen

• 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.