From: David VanHorn <microbrix@gmail.com>
To: Microcontroller discussion list - Public. <piclist@mit.edu>
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Date: Fri, 22 May 2020 08:23:07 -0700
Subject: Re: [EE] Light bulb moment (literally)
Thread-Topic: [EE] Light bulb moment (literally)
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My first bike had a combination bulb and fluorescent light.  6: tube. The
generator had the usual 6V output for the bulb and 100V for the tube.
Never seen one like that since.  This was around 1967 or 68


On Fri, May 22, 2020 at 9:19 AM Chris McSweeny <cpmcsweeny@gmail.com> wrote=
:

> 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 th=
e
> 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*
> > --
> > http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive
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