Ebay Fake 10 Leds Dynamo Torch: Make It a Real One!

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Introduction: Ebay Fake 10 Leds Dynamo Torch: Make It a Real One!

If you want to buy a dynamo torch from ebay, beware: they are most likely to be fake! Just like the one I bought: there is a crank dynamo, but there is no built-in rechargeable battery, just regular batteries. The crank works, but it only powers the leds "live", it doesn't charge anything.
I had to do something with it, so I "pimped" my torch :)

Material List:
1 led
1 supercapacitor (1F, 5,5V)

Step 1: Open the Torch

First remove the "head" by pulling it. Be gentle, because the wires are thin and you don't want to break them by pulling the head off. Just pull it enough to separate it from the body about 1cm.
Then remove the 2 screws. Be careful when separating the 2 halves because the spring of the crank is very hard.

Step 2: Change the Circuit

Once you opened the beast, you have to change the connections.

Before changing the connections, it had 2 positions:
- position 1: the crank powers the leds
- position 2: the battery (3 LR44 batteries) powers the leds

After it will have the following positions:
- position 1: the crank charges the battery
- position 2: the battery powers the leds

And now, the schematics, very basic:
I have inserted a led in order to prevent the capacitor from discharging to the crank. And it turns on when the capacitor is being charged. There are many instructables already that explain this, so many thanks to You people for inspiring me in saving my fake torch!

Step 3: Put Everything Back Together

After modifying the connections, put everything back together. If you want to have some light immediately, I suggest you charge the capacitor before, putting it in the torch.

Voila! You have now a real 10 leds dynamo torch, with built-in rechargeable battery.

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    17 Comments

    LOL i just remembered setting up this account and making that username.

    Well, I thought I was going to be able to try this but..I don't think I can. In looking at this instructable I don't feel like I have the info needed..

    Hey!
    I am seeing quite a lot of these rechargable torches lately.
    I see that 'supercapacitors' are THE thing now.
    But the reason I posted this comment was to tell you that such torches as shown in the picture exist.
    I have one with a similar charging system that has 3 LEDs. It glows bright and works for about 8 hours. you need to charge it for a few minutes only. I have charged and discharged it multiple times too.
    I didn't want to deconstruct it because it has complicated mechanics and I wouldn't be able to get it back together but apparently, the protuding lever that you see in the image has to be pressed multiple times quickly. This spins a dynamo and stores charge. I am not sure whether the torch uses capacitors or batteries.
    The point was just to tell you guys, that there are torches like these ones that aren't fake! I got mine for about $6.

    how long will LED glow after full charging of 1F capacitor?

    Can i use a rechargeable battery instead of the capacitor? Coz i could not find that specification...

    Yeah... batteries will probably just act like huge resistors... I made one of these myself and the battery approach didn't work. I mean the battery charged, but didn't light anything :D I'm a noob though so if you succeed let us know. I used two 500nf capacitors and those did work.

    The only difference is that caps release their energy more quickly.

    yeah... but you're limited by the amps you get. with a battery you'll most probably need to deliver more than is possible from such a tiny thing. maybe if I kept on pumping it, it would eventually work (and for longer than the capacitors) but it seemed it just didn't really go into the battery and rather just magnetically charged the coil or something and dissipitated.

    I don't think so because a battery is not a capacitor. You have to use some electronics to charge a battery.