MEP EP#237: Ice Cream Solder Paste Equipotential

<h4><a href="https://macrofab.com/blog/mep-ep237-ice-cream-solder-paste-equipotential">MEP EP#237: Ice Cream Solder Paste Equipotential</a><br></h4><h4>Parker</h4> <ul> <li>Cat Feeder Unreminder <ul> <li>Started designing the parts and symbols in Eagle. </li> <li>Will post more on twitter as I build the components and put together the symbols</li> </ul> </li> <li>Garage Door opener hacking <ul> <li>Converting my normal style garage door opener to a “jackshaft” style opener</li> <li>Why? </li> <li>LiftMaster, Chamberlain, Craftsmen are all the same </li> <li>Mine is a Liftmaster Formula 1 <ul> <li>Belt drive need to convert to chain drive to attach to the jackshaft</li> <li>All of these use similar drive mechs</li> </ul> </li> <li>Other things that are needed <ul> <li>Garage door auto lock <ul> <li>SureLock Garage Door DeadBolt</li> </ul> </li> <li>Cable tension switch <ul> <li>LiftMaster 41A6104</li> </ul> </li> </ul> </li> </ul> </li> </ul> <h4>Stephen</h4> <ul> <li>High voltage low current measurement <ul> <li>Resistive dividers? <ul> <li>Caddock 1776-C681</li> <li>10M ohm</li> <li>0.1% tolerance with 0.05% matching</li> <li>Low PPM</li> <li>This method is ok but requires a rather large current sense resistor which is not great.</li> </ul> </li> <li>Floating supplies <ul> <li>This is how multimeters work. The reference is floating.</li> </ul> </li> <li>Isolation solution <ul> <li>May go with an isolated solution - basically a power supply that isolates the secondary.</li> <li>Isolated digital communication down to LV side.</li> </ul> </li> </ul> </li> <li>Tests for pcb shielding <ul> <li>Did a shield plane test on a new pcb assembly.</li> <li>Top and bottom pours that respect clearance rules.</li> <li>5mm pitch via stitching.</li> <li>All terminate to one pin on a 2 pin header. <ul> <li>Second pin connects to a plated bolt hole that goes to chassis.</li> </ul> </li> </ul> </li> </ul