LDR circuit.. no luck :(

Hi Guys, I'm hoping this is the right place to find some help.
I'm undertaking a project for school where I have to design and construct an outdoor lamp powered by solar electricity. The circuitry itself is not a big deal and I'm allowed to purchase one that is already made.

I went out and bought an "outdoor solar shed light"
(this one: http://www.jaycar.com.au/productView.asp?ID=SL2715&keywords=solar+light&form=KEYWORD).

It came with a toggle switch which I unsoldered (and melted in the process).

I thought it would be as simple as soldering an LDR in place between the red and black wires that I had removed the switch from. This didn't work for some reason. If I touch the red and black wires together the circuit is completed and the light will turn on, however if I place an LDR in between the light does not turn on. I've gone out and bought more LDRs to make sure it was not broken but none of them worked.

I have very limited knowledge on electronics and circuitry so I'm basically stuck. Does anyone have any ideas on how to make this work?

Thank you in advance
PhiLep

 

Also, I need the light to turn on when it is night time.. not the other way around.

 

Sorry if I was unclear, by design and construct I meant the actual base of the lamp and all of the "wood" side of it, the electronics I don't have to build myself. I'll have a search of what you suggested and hope I can figure somethig out. If I were to post pictures would you be able to guide me as to what goes where?

Thanks for your help

 

These two wires are where there was a toggle switch:


This is where the battery pack connects:


Battery Voltage (Ni-Cd AA 600mAh 3.6v):


This is where the solar panel connects:


Solar panel connected:


The two wires touching = light is on:


Not touching = light off:


LEDs that are used:


Completely dismantled:


Closeup of the circuit board:


This is what I was trying to do with the LDR (didn't work):



And this is the lamp that I'm building. My plan was to put this lighting unit inside of the acrylic housing (white semi-circle thing) and then solder the LDR to a long wire and run it through the back of the wooden base and outside a drilled hole so that it would only detect sunlight and not the light inside the housing.



Please let me know if you need any other pictures or closeups or if anything is unclear.

 

I also looked up the light operated relays and skipping through all of the stuff I don't understand (schematics and all of that) I found this..
http://www.jaycar.com.au/productView.asp?ID=KG9090

That store is where I also bought the light from, would I be able to use this?

 

All of that is correct, the red and black pair of wires do illuminate the light when shorted.. this is where the switch originally was (which is now melted). I have no idea what the board is for, I'd assume it's just to wire everything up together?

I took some photos but I still think it might be a bit hard to see.. the tall black things are transistors (I think.. they have three legs) labelled "A1, A2, A3, A4". Then there's 8 resistors labelled R1-8. R7 has some U-shaped yellow thing soldered into the same holes. There is also some small cylinder-shaped black thing which is labelled as "D1". That's all of the components other than the battery-pack adapter socket thing and the solar panel jack socket.

There's also four holes in a row where the LED strip and the two (switch) wires are connected.

The holes are labelled as (in order): "K / L- /L+"

K = Red Switch Wire
/ = Black Switch Wire
L- = Black LED strip wire
/L+ = Red LED strip wire.

Hope that helps out if you can't read the pictures.

Here's the pictures:

 

The last photo is probably the most clear

 

Hi KrisBlueNZ, here are the markings that I can see:

Transistors (all):
58050
D 331

Diode (Black Cylinder thing?):
IN5819 (or 1N5819?)
MIC


Unknown thing (Yellow U-shaped component):
103


as for the resistors, they are really small and don't have any letters or numbers on them. There are a few different ones...

Here are the colours of the stripes from left to right:

R1:
Green-Red-Black-Red-Red

R2:
Brown-Brown-Black-Red-Red

R3:
Red-Red-Black-Red-Brown

R4:
Brown-Black-Black-Red-Brown

R5:
Orange-Orange-Black-Orange-Brown

R6:
Brown-Red-Black-Blue-Green

R7
Brown-Red-Black-Black-Brown

R8:
Brown-Red-Black-Red-Red


It was difficult for me to distinguish between blue and black so some of the blue's may actually be black and vice versa, sorry.

 

and of the two options, whatever you think is the easiest option.

 

Oh wow I completely missed that, sorry!
I was wrong.

A1:
S8550
D 331

A2:
S8050
D 331

A3:
S8050
D 331

A4:
S8050
D 331

only A1 is different, A2 A3 and A4 appear to be the same.

Sorry about the confusion.

 

I actually have no idea how to read schematics diagrams :/ I am really bad at electronics. Do you think if I show the diagram you drew to a person working at an electronics store (such as JayCar) they would be able to source all of the parts and tell me what goes where?

 

Hmm I really don't know anyone that would be able to help me put it together. The teacher was the one who told me to just put an LDR in place of a switch.. haha. I have some people in my family that are electricians, do you think they would know this stuff about circuitry?