I used one of these several years back - when the only high intensity LEDs
were still red :)

The principle is sound, and the device works well - but not (ideally) for
prolonged use - you can get pretty fed up with shaking the thing violently
every minute or so. It took quite a bit of shaking to get a full charge, and
the capacitor leaks (charge) so it has to be re-charged when needed. As an
emergency backup, it is almost perfect.

I also tried one that cranked a magnet inside a coil by winding a handle -
less convenient but less undignified.

Although I would recommend the device as an emergency backup torch, I cannot
say anything about the quality of those on offer! My own solution was a
standard Maglite with an LED instead of a W-Kr bulb.

Paul.

----- Original Message -----
From: "Roger Gosling" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Wednesday, June 18, 2003 9:25 AM
Subject: A new torch for the kit?


> Has anyone on the list come across this or better still got one?
> Roger
>
> -----Original Message-----
> From:
> Sent: Tue 17/06/2003 22:21
> To: Sub Brit Postings
> Cc:
> Subject: [SUB-BRIT] A new torch for the kit?
>
>
> Somebody will no doubt correct me on my assessment of the novelty of this
but I believe an interesting torch has just become available in this
country. "The Forever Flashlight". It combines old and new technology to
produce a waterproof sealed torch without batteries that you shake for 15
seconds  to give 5 minutes of high power LED light. The charge is held on a
capacitor.There are loads of sites in US (which was the origin of the spam
that alerted me to this) but not much in the UK yet. I found the one below
on Google.
>
>
http://www.gadgetsuk.com/xcart/catalog/category_259_Torches_and_lights_page_
1.html
>
> I'd be interested to know if anyone buys one and what they think.In
America it comes in two sizes. I think it needs clarifying with the UK
seller which is actually on offer at the price given.
>
> Without wishing to insult anyone's intelligence the simple science for
this piece of kit is reproduced below from an American website for those of
gadget inclination. It is widely available in America but  seems to have
appeared here only this April.
>
> Technical Information
>
> What is "Electromagnetic Induction" and how does the Forever Flashlight
use it?
>
> The Forever Flashlight uses the Faraday Principle of Electromagnetic
Energy to create the electricity it needs to charge itself. The Faraday
Principle describes how a magnetic field can produce electric current in a
wire that passes through it. When the Forever Flashlight is shaken, a magnet
slides back and forth through a copper wire coil. The electricity produced
as a result is then stored in a capacitor instead of a battery.
>
> What is a "Capacitor" and why does the Forever Flashlight use one?
>
> A capacitor is a basic electronic component that stores electric charge. A
capacitor is used in the forever flashlight instead of a battery due to the
fact that power is always available by shaking, thereby requiring less
electricity storage than normal flashlights. The Forever's capacitor holds
enough charge for over 5 minutes of bright light without further shaking.
>
> What is an "LED" and why does the Forever Flashlight use one?
>
> An LED, or "Light Emitting Diode" is an electronic component that emits
light when an electric current is applied to it. LED's, long used for
electronic indicator lights, have become very popular for other lighting
applications over the past few years in everything from street lights to
roadway hazard lights and vehicles. A big reason for their popularity is
their efficiency and lifespan. An LED is many times more efficient than a
halogen or fluorescent bulb, uses much less power, and lasts for up to 10
years - a perfect match for the design of the Forever Flashlight!
>
>
>