Flashlight without batteries

[faris]

hi all,
first of all i'm happy to become a member in this ammunity which is of course contains a lot of information about electronics, so i will be a good member and i will be helpful :)
second, I'm searching about project called flashlight with no batteries, if any one has some information or websites about it please tell me.
thanks :)

[mixos]

Hi faris :D , Welcome to Electronics Lab Community!!

What exactly will be the power source? Something like this:

Dynamo Powered?
http://www.campingsurvival.com/dynflaswitba.html

Shake Flashlight
http://k3www.com/shake-flashlight.html

Faraday's Principle (the same principle with the above)
http://www.thinkgeek.com/gadgets/lights/5a9f/

Also check this conversation here:
http://www.electro-tech-online.com/viewtopic.php?t=5998&postdays=0&postorder=asc&start=0

Tell us if you find or build something else.

[faris]

thank you my dear
what you answer is exactly what I want
but unfort. i don't knew the circuit or how it is build?
if u knew something tell me please :)

[Dosbomber]

The UK magazine Everyday Practical Electronics (EPE), of March 2003, had an article on building your own LED flashlight powered by a few turns of a unipolar stepper motor you might want to look into if this is the sort of device you're looking to build.

The magazine is available on the web (www.epemag.com) if you want to check it out.

[faris]

thank you for youe attention,
really i found some clear picture about this project in this link

http://www.electro-tech-online.com/viewtopic.php?t=5998&postdays=0&postorder=asc&highlight=flashlight&start=30
i want u to read what was wrote there and give me the idea and the steps of design this project
and this is the main idea of the project
COIL -> Bridge Rectifier -> Capacitor -> Current control -> LED

[MP]

I have not really been following this thread, but why not just use a one transistor radio receiver circuit and rectify the received wave with a diode to use it as a power source. (radio waves are everywhere). You should be able to get about 3 volts from this.
You then only have to connect it to a low draw bulb or LED. 8)

MP

[faris]

sorry, i didn't det your point, would you explain more, how can i use transistor radio receiver circuit instead of coil as power source??
8)

[MP]

rectify the radio signal so that it is DC. Actually, I used the term "1 transistor" to mean simple, but I am not sure that you even need a transistor.

MP

[faris]

thank you very much for your point
but i don't want to use radio wave

i want to use i said before magnetic coil which produce ac current then by using bridge diodes (full wave rectifier) concert it to dc current, after that the dc is stored in a capacitor, then discharge it to some leds,

of course i use the current control to control this discharging, by my problem is how can avoid discharging in the opposite way of the daiodes?? :)which element can i use resistor or what???

[MP]

glebka11:
Receive the wave with an antenna into a vari-loopstick, then rectify the signal with a diode and a few filtering components. You will not get much current, but I am sure it would light a bulb or LED if you tune it well enough.

MP

[MP]

I do not have a ready made circuit for you. I would have to design it and I do not have the time to jump into another project at the moment. When I have the time available, I will put something together and upload it to the forum.

MP

[bogdan]

one thing i have thought of would be to use a super cap and some rechargable batteries, and a led driver. this way you could charge the cap, adn also the batteries. the batteries will last longer than the cap. you oculd also add a solar cell to charge it from light.

an interesting idea would be to create a rechargable flashlight that can get energy from various forms...like shaking, light, heat(?! maybe it would be possible?) and some other stuff.....so it would be some sort of universal powert flashlight....
i have thought of this, but i don't have the time now to try and experiment some ideas.

one way would be to make something really small and light to be very portable....

[Guest Yevgenip]

My dear friend, hi! I'm a newbie too.
About your project, there are a lot of alternative power supply sources, but if you want to make an impression and have some fun, use a radio reciver(like that other guy said).
Just connect a diode bridge stabalizer to the output of a simple diode radio reciver (Tell me, and I'll explain how to build it).
That's it!
Now you can use The DC output to power anything small.
It's chip and mobile, but tends to have power blackouts in low reception areas.
Good Luck! ;D

[Guest Yevgenip]

Oh, I forgot!
You can also make one of those flaslights that by shaking your hand for a minute. It uses an electromagnet coil to generate the power and a rechargable battery, so I dont know if you can classify this as "Powerless" Flashlight.
Shout for details! :D

[faris]

if we want to use electromegnatic by shanking which produce ac current then by using bridge diode we convert it to dc current, then store this to capacitor, after that discharge the capacitor to lamp, is it will be working or not???
second which can we use to control the discharging of the capacitor??
aslo is the idea of radio wave applicable here. instead of electromegnatic

[faris]

here is some pictures, see them ang give me your comments please

project.zip