KEY RING TORCH

In this project a Joule Thief has been used as it is small and pocket size.

It also give long life to the battery.

The PVC cover of a toothbrush head is used as the container.

Discarded Motherboard Battery of 3 volt is used as a power source,

as it is small in size and packs a lot of power.

A micro switch is used because it cannot stay ON in your pocket by accident.

This can also be used as a Continuity Tester with a slight modification.

Step 1 List of Parts.

1. A small PVC container.

1. Micro Switch.

1. Disc type PC. Motherboard Battery.

1. Transistor BC 337

1. Electrolyte Capacitor 10uF / any Voltage.

1. Disc Capacitor 470pF

1. Resistor 2.2K

1. Ferrite core (taken out of a CFL light)

10. Turns of double 0.5mm copper wire for the coil.

1. Extra bright White 5mm LED.

Comments

[ray_Bond]

Good one Bro nice way of displaying project work........................

[qs]

Good job - nice application of the JT idea.

The sensitivity of the continuity checker can be improved by disconnecting the wire from the resistor to the base of the transistor and putting the test leads there - you'll then be able to tell resistances up to 15k by the brightness of the LED.

Naturally you'll have to replace the switch!

[Dipankar]

Thanks for your valued advice.

[rimar2000]

Good work, Dipankar, as always!

[mathman47]

Nice job. A multitasking Instructable no less. Unfortunately I already have both of these in other forms so I won't be making them, but very good ideas and very green none the less.

[Dipankar]

Thank you Pal.