If the voltage levels are unstable (ie: power stays on, but the particular voltage degree may differ a lot from the 220V common), then I think that's the kind of circumstance exactly where an AVR is useful. A UPS unit in your router and modem is usually fantastic all through https://event14815.fitnell.com/74601389/how-uninterruptible-power-supply-can-save-you-time-stress-and-money