I am going to use a 6 volt battery to power about 8 leds the white or color changing leds not sure which but both are rated at 3.3 to 3.8 volts. I want the photocell to turn the LED's on around dust and off at dawn.
I am wondering if this would work and would I have to change things around to make this circuit work.
Sorry I don't know much about electronics, so be kind if I am way off base. I found the drawing here on this site and mod, it some to see if you guys think this might work for what I want to do.
The Photocells are Cadmium Sulfide that came from radioShack they have no values on the package, kind of a grab bag of 5 different values. I do have a digital voltmeter I guess I need to check them and see what values they are.
Other information I have the battery is a 4.5 AH, 6 volt and the Leds are 3.3- 3.8 volts at 25 ma's.
If the can get the circuit to function I want to add a solar cell to keep the battery charged but will be another project.
The Photocells are Cadmium Sulfide that came from radioShack they have no values on the package, kind of a grab bag of 5 different values. I do have a digital voltmeter I guess I need to check them and see what values they are.
Other information I have the battery is a 4.5 AH, 6 volt and the Leds are 3.3- 3.8 volts at 25 ma's.
If the can get the circuit to function I want to add a solar cell to keep the battery charged but will be another project.
Yes the value is in OHM's I have not purchased the transistor yet, I thought I would wait and get that if the drawing would work, so the only thing I have on hand are the photocells, the battery, and a couple of the Leds, and some Misc, resistors.
Yes the value is in OHM's I have not purchased the transistor yet, I thought I would wait and get that if the drawing would work, so the only thing I have on hand are the photocells, the battery, and a couple of the Leds, and some Misc, resistors.
I plan on connecting about 6 to 8 leds, the voltage on the packages states that they are 3.2 to 3.8 volts and draw 25 ma, I plan on connecting the LEDs in parallel.
I plan on connecting about 6 to 8 leds, the voltage on the packages states that they are 3.2 to 3.8 volts and draw 25 ma, I plan on connecting the LEDs in parallel.
Maybe I am missing something but the LED's are the same voltage, the voltage I quoted are the operating voltages on the packages, they are all the same size. Sorry like I said I don't know much about electronics just trying to learn as I go.
Maybe I am missing something but the LED's are the same voltage, the voltage I quoted are the operating voltages on the packages, they are all the same size. Sorry like I said I don't know much about electronics just trying to learn as I go.
hi jake,
You say the LED's are in a pack marked 3.2V to 3.8V, the LED's are not matched.
I would suggest that you get a 150R resistor with the 6Vbty and check the voltage across each LED. You may be able to get a matched set. OK.
I have looked at some circuit options using the photo cell, its not the best choice of light/dark detector when using a battery power source, there is only a 100R change from light to dark.
I would suggest you look as some light dependant resistors LDR's or phototransistors instead of the photocell.
Ok on the photo cell I used another one out of the package and here are the results I got in the light measures 4k with my finger over the cell it measures 36k I am guessing that are better results.
Ok on the photo cell I used another one out of the package and here are the results I got in the light measures 4k with my finger over the cell it measures 36k I am guessing that are better results.
Ok on the photo cell I used another one out of the package and here are the results I got in the light measures 4k with my finger over the cell it measures 36k I am guessing that are better results.
hi,
Eventually found the part.
They call it a photo-cell, which is not quite correct, a photo-cell actually generates a voltage when illuminated,
thats what threw me a curve.
Its really a Cds photo-resistor.
For the circuit I must know how many matched LED's you are going to have to light.
hi aljamri,
The problem is the OP wants to use a 6Vbty, I suspect he wants to keep the current drain to a minimum.
Driving a relay would put an extra burden on the battery.