Dark-activated LED circuit modification needed

[cannibal]

hello

how to modify this circuit so insted of LED I connect new external circuit which uses it's won power source

I mean insted of activated LED the external circuit will be active

click here to see the circuit

???

 

[audioguru]

Replace the LED with the LED in a photo-isolator. Then the transistor in the photo-isolator can turn on whatever you want.