How do I add a photo sensor to a LED nightlight?

ken2400

Enlightened
Joined
Oct 30, 2006
Messages
227
I have been making some LED night lights. I now want to put a photo sensor on them. I have some old 4 watt night lights with a photo sensor BUT they did not work. I believe I am not using enought current? It just a transistor - photo cell - resistor.

Should I change the resistor value. Now it is a RGB then gold one so it is 25 then 7 for the multipler? Should I up it or lower it?

The transistor is 40
10
TagT4

Thanks
 

carbine15

Flashlight Enthusiast
Joined
Nov 20, 2005
Messages
1,986
Location
Slaughter, WA
the only photocell I have is hooked to a potentiometer to adjust the amount of light required for activation.
 

Lynx_Arc

Flashaholic
Joined
Oct 1, 2004
Messages
11,212
Location
Tulsa,OK
I recently stumbled onto some LED nightlight replacement bulbs that essentially screw in place of the 7 watt bulbs found in most cheap nightlights. These have 3 5mm LED and claim to cost 25 cents a year when operated 12hours/day so for 50 cents a year 24/7 I put one in my fridge door where the water/ice dispenser is and lights up the kitchen and another in the living room over the answering machine. I got the bulbs in 2packs at walgreens for $3.99.
 

ken2400

Enlightened
Joined
Oct 30, 2006
Messages
227
I wonder if they would work?
http://www.walgreens.com/store/product.jsp?CATID=100770&navAction=jump&navCount=1&id=prod2419636



Lynx_Arc said:
I recently stumbled onto some LED nightlight replacement bulbs that essentially screw in place of the 7 watt bulbs found in most cheap nightlights. These have 3 5mm LED and claim to cost 25 cents a year when operated 12hours/day so for 50 cents a year 24/7 I put one in my fridge door where the water/ice dispenser is and lights up the kitchen and another in the living room over the answering machine. I got the bulbs in 2packs at walgreens for $3.99.
 
Top