MEP EP#237: Ice Cream Solder Paste Equipotential
Parker
Cat Feeder UnreminderStarted designing the parts and symbols in Eagle. Will post more on twitter as I build the components and put together the symbolsGarage Door opener hackingConverting my normal style garage door opener to a “jackshaft” style openerWhy? LiftMaster, Chamberlain, Craftsmen are all the same Mine is a Liftmaster Formula 1Belt drive need to convert to chain drive to attach to the jackshaftAll of these use similar drive mechsOther things that are neededGarage door auto lockSureLock Garage Door DeadBoltCable tension switchLiftMaster 41A6104High voltage low current measurementResistive dividers?Caddock 1776-C68110M ohm0.1% tolerance with 0.05% matchingLow PPMThis method is ok but requires a rather large current sense resistor which is not great.Floating suppliesThis is how multimeters work. The reference is floating.Isolation solutionMay go with an isolated solution - basically a power supply that isolates the secondary.Isolated digital communication down to LV side.Tests for pcb shieldingDid 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.