Dynamo Hand-Crank USB Cell Phone Emergency Charger

Pros: Great price
Good build quality
Does what it's supposed to do, power your usb devices

Cons: It takes a lot of time to charge your devices, but ideal for emergency situations
Led is placed close to the usb port, this isn't a problem with normal usb connectors

Other: Great for on a vacation because you've got plenty of time there. If there's a power outlet somewere around i would definitely use that

Pros: It's a useful item and the price is right. It's nice looking and when enough power is generated the light will indicate this.

Cons: The cons however are, in my case I have to use it when my phone is off. When I charge it for 10 min I can use it 5 min. So it's GREAT when your phone is out of power and you MUST make an emergency call. Hope the emergency aint that your arm just fell off...
Sometimes it skips a bit, this aint nice. It feels like it could break really quickly.

Other: It could be a lifesaver but I'd def not put my life into the hands of this device...

Pros: works great. build quality is satisfactory, it as a small led indicating the charging. perfect for charging your cell phone etc etc. it's a really useful item.

Cons: WTF? I bought mine for 2.99 here at DX... now it's 3.30?! it doesn't have an internal battery.. but that would be a different item.

Other: it's cheap and extremely useful. get it.

Pros: It works. I tested this with a PDA (Qtek S200). This PDA needs about 300mA before the actual charge cyclus is started. You can feel it very good on the crank; first of all it's not so tough, but after the PDA starts charging (2 seconds after the charging led lit) it's hard working to get the crank around. After 5 minutes I couldn't get it around fast enough...
The led on the charger is RED, and always on during use.

Cons: The led should switch of after a device is connected. This power could better used for charging.
Build quality is OK, but the mechanism is not very strong. Start up gently otherwise you will break the gear.

Other: Great but only for emergency charging.

Pros: +low price +irreplacible in extreme situations +good enough build quality +easy inner structure

Cons: -led light is red for some reason, but white light would be much more useful -plastic gears, most weak part of this device -difficulties in use with some cell phones -not best convenience of use, you will tire to twist the handle soon enough

Other: If you are a tourist, or spend much time far from the electrical network, it will be very useful for you. Device has some minor lacks, but they are not very important. Best choice if you have many USB devices.

Pros: Handy device for emergency and toying with electricity. A good learning expriment about regulators for those learning electronics like me. I knew nothing about regulators before buying this crank. I made a simulation of the inner workings and found the problem before the actual broken contacts... read on. :)

Cons: Build quality is very low. I soldered many cold contacts again inside the device. The regulating 6V zener-diode (orange glass component) did not have contact to the transistor (black with three legs component) and the rest of the circuit. The transistor had broken off from the circuit board because the casing had forced it to move! This causes the voltage to go as high as 12V which is too much for USB. But luckily it all was fixable and now it produces around 6,3V when nothing is plugged in. Also the mechanic side is low quality. One of the gears inside is bent. The generator's gear was not well adjusted to place and contains small plastic manufacturing artifacts that at first cause resistance but soften after some cranking. The led's color is RED and it also wastes some current. Solution for this is in below.

Other: Don't use this if it produces over 7V of voltage when cranking without plugs in. It probably wont succeed in charging anyways due to protections in devices. If it first starts charging and then suddenly eases up and the charged device stops charging... there are problems inside. Fix it or request a new one. The more the charged device needs power the harder you actually must crank. So there are differences when charging different devices. Charging a NDS lite is harder than for example Nokia 6730. Good luck!

Pros: You can charge any usb chargeable device in emergency situation, without depending on sun, or any other battery operated device (like laptops or external solar batteries or something like that) It's enough cheap

Cons: Very very very very low charge. I have been 5 minutes spinning the dynamo and my nokia 5800 said 'charging' all the time, but with the software 'battery life' I could see the battery level has not increased even 1% Red led is wasting current. Maybe with a white one it could be used like a flashlight, but this red led is a waste of current and money...

Other: Maybe useful in emergency situations if it doesn't break before.

Pros: By far this is the perfect usb emergency hand crank dynamo, i like the small weight pocket size feature, im actually keeping it in my backpack cus i pretty much take it everywhere i go. Its small, Reliable and no batteries needed

Cons: When i got mine the crank didnt work, i took it apart and saw that one of the gears was not touching so i took it apart and pushed it in place, now it works. mine chipped when i opened it, matterial doesnt seem sturdy but who can complain with the price? other than that no real problems

Other: Its an emergency item you can depend on if you use it correctly and dont abuse it because it will come in handy if you have any item that connects to a USB port, such as Razr, BlackBerry, and some other smart phones.

Pros: I reckon there is NO pro's with this device at all.

Cons: i bought this usb hand crank for fun but i still thought it would work fairly well, but when i recieved it i plugged a iphone usb cable into it and tried charging my iphone i spun the handle round and round but it would charge and after about 10 minutes of spinning i started to smell smoke from the actualy device itself, unless this a defective product then this is complete waste of money.

Other: While i was shopping online it looked like a good buy for emergencies but when i received this package and tested this device out for myself i found out it is a waste of time and money it wasnt worth ordering and waiting for it.

Pros: This device is very nice *in concept*.

Cons: It is very poorly built: after my second time using it, the plastic casing cracked around the well of one of the two screws holding it together. The gears rely entirely on the case to be held in place, so if you spin the handle too hard, you place too much stress on the case. I had to glue it back together.
The power it puts out may be unregulated:
after using this device a few times, I have noticed that the battery life on my cell phone (LG Dare) is about half of what it used to be. This is a pretty sudden drop. Closer inspection of the battery found it to be slightly swollen in the middle. I think one or two of the cells inside may have burst because of charging with this device.

Other: Buyer beware! While I thought I should be able to get a good dynamo charger for this price, this isn't the one.