Ran 6 drops in a 1920s house with old knob and tube and my toner started picking up the wiring itself
Client in Cleveland, house built 1924, plaster walls everywhere. I was fishing a run to the back bedroom and my tone generator was screaming on a pair I hadn't touched. Spent 40 minutes chasing a ghost before I figured out the knob and tube in that wall was running parallel to my fish tape. Bought a cheap clamp meter the next day. If you're doing old houses, walk the wall with a stud finder first, half those cavities are packed with live cloth wiring. What do you guys use to tell your cable apart from old house wire without opening the wall?