Simple LED circuit help pls

Thread Starter

sztriki

Joined Feb 10, 2019
12
This is exactly how I fluffed it up initially, forgot to add the first resistor, hence the dead first LED, spot on. But after replacing the first LED and adding the resistor it still faded out, granted, the first LED lit up properly this time. I will do exactly what Spinnaker suggested, go one by one, add the resistor, test with a battery and if they all work individually then sort of train-track them together. I can't really take a convenient photo of the wiring, cuz it's spread out on a 60 cm long wooden strip so can't capture it all, hopefully taking it slow this time will help.
 

BobTPH

Joined Jun 5, 2013
11,515
But the rest of the wiring is incorrect as well. Here is how it should be:

upload_2019-2-17_14-12-14.png
Do you see the difference?

You should one end of all of the resistors connected together to the battery terminal, and the other end of each resistor connects to one LED.

Bob
 

BobTPH

Joined Jun 5, 2013
11,515
Just give a picture of the beginning of end of the strip from the opposite side where the wiring can be seen, near the battery, and including several LEDs, and we will be able to confirm the wiring.

Bob
 

Thread Starter

sztriki

Joined Feb 10, 2019
12
But the rest of the wiring is incorrect as well. Here is how it should be:

View attachment 170353
Do you see the difference?

You should one end of all of the resistors connected together to the battery terminal, and the other end of each resistor connects to one LED.

Bob
Daaaaaaaamn, told you I'm a total dummy. You're absolutely correct. Here's a photo, the negative wire of the power socket came off, but now that I see the two schematics compared it makes total sense. Thanks very much for that!
 

Thread Starter

sztriki

Joined Feb 10, 2019
12
So, I took the whole thing apart ,tested every LED, found 3 more dodgy LEDs, then rewired the whole thing this time exactly as the drawing, lo and behold, it's alive! Works perfectly, all I need to do now is finish a casing and the frame for the picture and it can go on my wall.
Thanks very much for everyone who contributed, I'll post a picture of the completed full thing just as a closure!
 

iONic

Joined Nov 16, 2007
1,662
The LEDs are the same except for two that I've blown when the 9V battery was wired to them without a resistor. I don't have a multimeter to test the resistors but I'll take the whole thing apart and test at least the LEDs with a 3V battery and take it from there. Then I'll try and make a tidier wiring, I basically soldered the legs of the batteries to each other with the resistor wherever it was applicable.
No multimeter, no problem. what color are the bands on the resistors and are they all the same? If your still wire the same the colors should be Orange, Orange, Brown. A gold band may follow, which is the tolerance.

OOPS! Looks like you have it working!
Photo looks pretty cool!
 
Last edited:

wayneh

Joined Sep 9, 2010
18,104
Here it is then, fully functional, up and running. Thanks very much again everyone for your help!
Very cool effect. You might consider placing a reflector shade over the LEDs so they are not seen directly from the front, and more of their output gets directed onto the art.
 

spinnaker

Joined Oct 29, 2009
7,830
Very cool effect. You might consider placing a reflector shade over the LEDs so they are not seen directly from the front, and more of their output gets directed onto the art.

I don't know. I kind of like seeing them. Looks good in the photo anyway.
 

Thread Starter

sztriki

Joined Feb 10, 2019
12
Yeah, without a shade they can light up things in the room with the viewer. Hmmm... isn’t that a risk to your eyes? I suppose the intensity is fairly low.
Thanks guys!
I'ts quite far away, on the wall opposite my bed, so should be cool, not gonna go on too often anyway. :)
 
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