An electrical timer automatically actuates an output electrical load device such as an electric light according to a program stored as markers in a memory unit over a 24-hour interval, whereupon the program is recycled. By actuating one or more electric lights within an empty dwelling, an illusion of occupancy is thus conveyed to an observer. In the preferred form of the invention the memory unit is a recirculating shift register. A daily variability of the timer output is provided to prevent precise daily replication of the load device duty profile. One version causes the program output to be delayed by 15 minutes on alternate days by alternately taking the output from the last or the next- to-last storage element of the shift register. The stored duty profile is in 15-minute blocks. A second version uses 30-minute blocks and minimizes possible output distortion during the transition from normal to delayed display by using two timing pulses 16 minutes apart to display the program output on alternate days 8 minutes early or 8 minutes late. The second version allows use of a smaller amount of memory storage.
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