Offline Alexa Nurse Call Device (2nd Generation)
This document outlines the second-generation design for the offline Alexa nurse call system. This device requires no coding or soldering if following the steps listed below. This system allows Alexa to work offline to control most hospital call light systems that work off a 1/4" stereo plug input. For more information on how this system works, please refer to this blog post. Listed below are all the parts required (with links): ZigBee Relay ¼” male to ¼” female mono stereo cable Project box 12V power supply Steps for assembling device: Step 1: Take the ¼” male to ¼” female mono stereo cable and cut the wire to separate the male and female ends. It is best to cut the wire so the male end has 2/3 rds or more of total wire length (cut closer to the female end). Once the wire has been cut, strip the wires as shown in the figure below, so both the male and female ends have two bare wires each. Step 2: Take the 12V power supply and cut the barrel jack off th...