House is ~50 years old. Copper Wiring. On one 20a circuit there are a number of duplex boxes. On three adjacent to each other the voltage reads 120 -- ~40 -- 120. The previous owner switched one box to a single receptacle and switch. And wired to the switch a lamp (incandescent) in a new skylight. The operation of which has always been problematic.
I tracked down the low voltage recaptacle when I move the refrigerator plug to that outlet.
Any thoughts on this? Thanks.