Ideas I checked include: 1.  The photocell controller in the power pak used
for low voltage outdoor lighting - the photocell is on the 120 volt side of
the unit.  2.  GM vehicles have a photocell which turns headlights on when
car is started and it's dark - one cannot buy just the photocell.  One must
purchase a wiring kit + photocell for about $35.
 
Thanks, Jim King, Riegelville, PA
 
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