Dynamo Led Flashlight

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EE majors, chide my circuits? OK, I have a basic general knowledge of electrical components/electronics/etc, but it's just that- basic. If anyone has time, I would really appreciate it if you could check over my alterations for problems. I have one of those dynamo flashlights with a really ridiculous light setup (2 modes- 1 white LED, or 4 white LEDs) and decided to change the 4 whites to 2 red and 2 UV. I have tested the LEDs at the corresponding zener voltages that will be installed to them, and they will be fine temperature-wise. I will heatsink them regardless. I believe the BJT is in-fact a BJT (NPN), and not a voltage regulator. It is shaped very similar to a 3494, but elongated. I have been considering replacing the cap with several more in parallel to flatten out the rectified wave. I'm also looking to get a matching 3.75 Li-Ion to replace the 3.6 NiCd. But I doubt the .15 volt difference will have any ill effect as it is. original http://www.geocities.com/delorean4905/orig-schem.jpg my altered http://www.geocities.com/delorean4905/new-schem.jpg You have to zoom in on the pics, they load as blurry at first. I have the zeners there because the single battery will steadily put out 4-6 volts right after charging. That surges to 8-10V while charging if the light is kept on. I dont plan on winding it while it's on, but someone else probably will. EDIT: Updated new schematic, fixed switch positions Neither circuit is good design. I'm surprised the orginal works at all. Putting forward-biased diodes directly in parallel is a bad idea. Unless the diodes are exactly matched in forward voltage drop, the one with the lowest value will hog all the current and the other will get none. Thing of the forward voltage Vf as a cliff: above Vf, current is not limited by the diode; below Vf, no current flows at all. The best solution is to have a resistor in series with each diode (instead of one for all), so that the current is determined by the applied voltage less Vf divided by the resistor. Small variations in Vf have little affect on the diode current, and diode brightness depends primarily on the forward current.
In your altered circuit, the zeners do nothing. The forward voltage of any of the diodes is much less than the zener voltage, so that establishes the voltage across the diode. Again, the best solution is to put a resistor in series with each diode and adjust its value to get the desired current using the formula
If = (Va - Vf)/R
EDIT: Your zeners are in series with the LEDs--that won't work. I have prepared a guidline for a zener-regulated multi-LED circuit I hope can help you:
http://img412.imageshack.us/img412/9229/document1hj0.png

What would be in your Zombie Preparedness Kit? Remember these are absolute necessities. They should be light weight, functional and as space saving as possible. My kit would ideally include, but is not limited to: ~MREs/Survival tabs/3600 calorie meal bars/Jerky ~Dynamo Powered/Solar: LED flashlight w/red filter/Radio/Single burner hotplate/ ~Ceramic water purifying canteen/Water purifying tabs-straws ~Pocket scope w/high magnification (IE: binoculars) ~Bug Spray/Sunblock ~Toothbrush/Highly concentrated soap ~Trauma Kit/Moleskin antiseptics/Iodine/Replace band aids w/liquid bandage/Tylenol-aspirin/Antibiotics ~Space Bags:Rain shell/Quick dry shirt/pants(pants zip into shorts)/WoolSocks/Pantyhose/Large Stay put undies/All weather hat/gloves/shoes-ditch improper cloths 4 packed 1s to lighten load ~Waterproof sleeping bag good for (-40' whether) can be used to collect rain water ~Road Atlas, Compass ~MultiUse tools: Leatherman/Shovel-pick-axe-crowbar/Knife-Whetstone/Sling shot (good for killing birds for dinner, why waste bullets) ~Electronic Flares ~Plastic Mirror(looking round corners) ~ShamWow Towels ~Survival Guide ~250lb nylon fishing line/hooks/Sewing Kit w/upholstery thread ~Gun/Bullets/Machete/Explosives Im a little lost on what to put for women getting their period... You cant very well pack all the crap yould need and the blood scent could bring zombies running... It would have to be lightweight/compact and preferably reusable (I know yuck). I thought of "Insteads" which are like plastic tampon cups that "catch" the blood. These could be reused in a pinch but they would have to be cleaned in between use to stave off infection... Any thoughts? Woot, what a note for me to end on ;D I should probably throw in hand warmers, masks, Potassium Iodate to protect against possible radiation/radiation detector, ductape, whistle, Solar Sleeping Bag, NBC (Nuclear, Biological, Chemical) Suit would be good but heavy and hot... chainsaw and gas

Super LED Wind Up Micro Dynamo LED Torch Flashlight? Do you know someone who sells this product in Australia? "http://astore.amazon.co.uk/cuteseller-21/detail/B000ON50EO" I really want this! However, they are British company and don't send it to Australia. Acutally it's seen at "http://www.amazon.co.uk/SuperLED-Micro-Dynamo-Torch-Flashlight/dp/B000ON50EO/ref=sr_1_14/203-6015753-4101563?ie=UTF8&s=diytools&qid=1183701967&sr=1-14". It must be this product! sorry I am stunborn. I am not sur if you can get this particular product but I do know you can get wind up LED torches from Kmart and big W.
I know because I have one in my power out emergency kit, Bought it only 3 months ago.
They work real well.

Where can I find prices for micro-dynamos? (they're the teenie little dynamos in things like wind up LED flashlights, human powered battery chargers, etc)? any country, just need a few prices, ta... Thanks folks, should have said, looking for manufacturers of microdynamos for quotations for a product being researched, not hobby stuff. Thanks anyway...:) This section also includes, but is not limited to cars, caps clowns, carpet motors, cool biker guy apparel,two cycle motor tune up tips, The Buddha,Clark Gable, Betty Gable, those little things that pop out at you, fashion, the origins of orange coast slipper removal, old ghost towns. And many others.

mechanical LED flashlights? According to wikipedia (http://en.wikipedia.org/wiki/Dyno_torch), a mechanically powered flashlight (or dyno torch) has a device called the flywheel that can store energy. From this, the user squeezes a handle to operate a small dynamo which supplies an electrical current to a miniature incandescent bulb for it to operate. My questions are: 1. How much energy does it store in the flywheel? 2. How much energy do we produce every time we sqeeze the handle? 3. Is possible for this mechanism to generate enough energy (with a few modifications if necessary) to make a mechanically powered hand held fan (ex: http://a248.e.akamai.net/f/248/5462/2h/amplestuff.safeshopper.com/images/w0fks5v.jpg)? Much thanks! 1. the energy is stored in the spinning of the wheel. Kind of like when you coast in your car. The real power is coming from the magnet rolling over the copper coils making a generator.
2. Very little. But if you made the setup better with real bearings and precession gears you could pull a lot more. Maybe around 1/4 watt.
3.Not even close to making the power needed to run a fan. Maybe again with a precession setup. Then i believe you would still have to use the hang pump to charge a battery .Then run the fan off the battery after you pumped it a number of times. More along the lines of hand powered radios.

Dynamo Led Flashlight is from category: Flashlights.