I have Xfinity internet using my own S33 modem and a 6g router.  My wife has concerns about emf and wants to turn off the wireless router at night.  I am up way before her and need to have internet access as I often work from home.  I want to be able to use a hardwired connection to my home office computer while the wireless router is turned off.  I thought I could use the second (bottom) modem port, but apparently cannot.  I tried simply unplugging the router from modem and plugging the ethernet cable into that modem port, but it doesn’t work either.  What is the best way to do this?