The Cyber-Spy.Com Usenet Archive Feeds Directly
From The Open And Publicly Available Newsgroup
This Group And Thousands Of Others Are Available
On Most IS NNTP News Servers On Port 119.
Cyber-Spy.Com Is NOT Responsible For Any Topic,
Opinions Or Content Posted To This Or Any Other
Newsgroup. This Web Archive Of The Newsgroup And
Posts Are For Informational Purposes Only.
Subject: Re: How to build a windup generator?
Date: Thu, 21 Nov 2002 18:24:47 +0000 (UTC)
NNTP-Posting-Date: Thu, 21 Nov 2002 18:24:47 +0000 (UTC)
User-Agent: tin/1.5.14-20020926 ("Soil") (UNIX) (Linux/2.4.19 (i686))
Michael Black wrote:
> "Dave" (email@example.com) writes:
>> I saw a circuit in a mag using a stepper motor. The motor was hand cranked
>> and the windings individually rectified. The dc outputs were paralleled and
>> had a 1 Farad capacitor across to hold the charge. The application was a
>> wind up LED torch if I remember correctly.
> That's intriguing. But did they make it wind-up, or did you have to keep
> cranking while the flashlight played? The neat thing about the Baygen radio
> (and it's imitators) is that you wind it up, and then the generator is
> powered as the "spring" winds down. I was under the impression it was
> similar to an old windup clock in design.
Some capacitors are getting rather large.
The Ultracap range from EPCOS for example.
10F@2.3V, max discharge current 3A, for around $6us.
Around 26J storage in around 5g.
(around 10% of the energy storage of a NiCd battery of a similar weight,
but a battery that can be charged at that rate weighs at least ten times
http://inquisitor.i.am/ | mailto:firstname.lastname@example.org | Ian Stirling.
"I am the Emperor, and I want dumplings." - Austrian Emperor, Ferdinand I.
Go Back To The Cyber-Spy.Com
Usenet Web Archive Index Of
The sci.electronics.design Newsgroup