In a fifty year old home with a 4 ton A/C central air the lights dim at startup and then continue to flicker for about 10 minutes. Dims for about 10 seconds and then returns to a normal. cycle gets longer you can stand by the condensing unit and hear the draw and watch the lights, this doesn't seem right can any one give me some direction. I haven't had it happen before, sometimes the lights dim at initial start up but I haven't seen it get going for like I said slightly over 10 minutes.

thanks in advance for any input

Blain