MEP EP#237: Ice Cream Solder Paste Equipotential

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.