This instructable is about How to make a LED Lamp with 121 LEDs with just 4 simple steps And the Light is very effective to lighten a room and only with a Battery of 6v - 9v.
Thing you"ll need -:
1. PCB with Holes
2. 121 LEDs
3. 9v battery
4. 330 ohms
Take led and connect them in series like shown in the picture.
Connect each line of leds with next line of leds
Connect the resistor with a led from first line and then connect to the battery
After completion of the fixing leds connect the Battery second terminal to the led of last line,if the led do not lighten up then exchange the terminal with each oter and after checking this solder all the leds with each other.