Please help.... LED content

[bennyboy]

I have these lights: http://www.superbrightleds.com/more...-led-30-degree-viewing-angle-380-nm-20mw/631/

I want to make battery operated strands of 20 and 10 lights.

I soldered the lights and tried to use a 9 volt battery clip with a 183 resistor but I could only light two lights with a dim third one.

So what do I do? My soldering is correct (anode to diode) but I cannot get them to light the string.

Thanks.

 

[(*steve*)]

Please read this:

https://www.electronicspoint.com/got-question-driving-leds-another-work-progress-t228474.html

Then come back if you still have questions.

 

[donkey]

I know very little on most things but I know that LED's should be at most 3-4 LED's long not 10 to 20. the thread steve has linked you too does help alot.

 

[Harald Kapp]

You can easily add 10-20 LED in series (or more). Only take care that the LED current is limited and that the voltage source delivers enough voltage for the full string of LEDs.
There are a lot of specialized LED driver ICs out there that are designed specifically for that purpose.

The LEDs bennyboy linked to are UV LEDs with a forward voltage of approx. 3.5V. There are several issues here:

1) UV LEDs emit light in th eUV part of the spectrum, thus the light is not visible to the unaided eye.
2) 10 of these LEDs in series require at least 10*3.5V=35V plus a bit of headroom for a current limiting resistor.

I wonder that you saw anything at all.