Introduction: LED Torch
Simple steps to convert your old bulb torch to LED Torch for just 1 $
Step 1: Step 1 - Parts & Tools
1.Power LED 1 Watt with heat sink - 1 No --------------> 10 Rupees
2.Resistance 10 Ohm 1 watt or 4.7 ohm 1 watt for more brightness - 1 No. -----> 1
3.Switch SPST - 1 No. 5
4.Diode IN 4007 - 1 No. 2
5.Resistance 1k - 1 No. 1
6.LED Red - 1 No. 1
7.Charger socket (Audio ) 5
8.Battery 4V 0.4 Ah (SMF) 35
Total --------------- 60 = 1 U.S. $
Charger you can use any old existing charger which is rating 5 Volts or can use mobile charger also for this you need to change the socket accordingly.
Note : If you want to have long duration , you can change battery 0.4 Ah to 1 Ah which will fit in the torch, the price is around 50 rupees in India.
Step 2: Step 2 - Circuit Diagram
Here is simple circuit diagram and , ray diagram of torch just to help assembling parts.
Step 3: Step 3 - Assembling
Before start assembling first you remove bulb , slide switch from the torch.
Make 6/5 mm hole for charging socket and 3 mm hole for red LED as shown in picture. cut the square hole for switch as required.
Make wiring as per circuit diagram, just see the photograph.
After completion of wiring do the continuity test & charging voltage , if all test are done then switch on torch , here you go live.
Step 4: Step 4 - Finishing
Finished torch, see charging indicator. Here we go live.