AC timer independent of AC circuit it's timing?

[Terry Parker]

I figured something out last night. There are four strand colors in
the set and five wires going out to them. I determined that one of
the wires is common to all of the circuits (return path). It would
appear this path is looped through the last three bulbs in the string.

So, if I interrupt this wire, I can disable the lights, but leave the
controller on (assuming the controller will still be running when the
light circuits are all failing -- I tried openining the controller to
get a better feel for what it's doing, but it's hardended plastic
molded directly around the circuitry). I could do this with a simple
A/C switch, but I would rather have it on a timer. The problem is
that the current through this line is not constant voltage, it varies
depending on what mode the controller is in. I assume this would mean
an AC timer placed in this line (by putting male and female plugs on
each side of the cut line) would not operate properly.

What I need is a timer that is powered on its own independently of the
circuit it is opening/closing. Anyone know of such a thing? Or, am I
missing another solution?