From: Chris McSweeny <cpmcsweeny@gmail.com>
To: Microcontroller discussion list - Public. <piclist@mit.edu>
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Date: Fri, 22 May 2020 08:17:31 -0700
Subject: Re: [EE] Light bulb moment (literally)
Thread-Topic: [EE] Light bulb moment (literally)
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It is, except that the maximum voltage is speed dependent. It is (was?) a
common modification to use one to supply 12V across two lights in series,
but with a switch to short out one of the lights at lower speeds where the
dynamo can't supply 12V.

On Fri, May 22, 2020 at 9:34 AM David C Brown <dcb.home@gmail.com> wrote:

> I have just realised that the traditional "dynamo" used for bicycle
> lighting (and which is really) a magneto) is, despite being sold as a 6
> volt machine,  a actually a constant current device.
> Since both voltage and frequency - hence reactance - rise
> approximately linearly with speed the current remains constant.
> __________________________________________
> David C Brown
> 43 Bings Road
> Whaley Bridge
> High Peak                           Phone: 01663 733236
> Derbyshire                eMail: dcb.home@gmail.com
> SK23 7ND          web: www.bings-knowle.co.uk/dcb
> <http://www.jb.man.ac.uk/~dcb>
>
>
>
> *Sent from my etch-a-sketch*
> --
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