Brad,
That kind of switch is called a "reed" switch. A magnet pulls it in from
one side (open) to the close side. You should be able to pick them up at
any radio shack/electronics store. Burglar alarm door switches are the same
thing: one reed switch (mounted on the frame), one magnet (mounted on the
door).
Oh, as an aside, those things are generally VERY low current. You will most
likely have to use it to pull in a relay to turn on your motor or whatever.
Bill
-----Original Message-----
From owner-spridgets at autox.team.net
[mailto:owner-spridgets@autox.team.net]On Behalf Of Brad Fornal
Sent: Monday, November 13, 2000 9:07 AM
To: WFO Herb
Cc: Mjsprite@aol.com; Spridgeteers
Subject: Re: magnet on/off switch
I have been looking to make an underwater DPV (diver propulsion vehicle).
The
power switch you see on the store models is enclosed within the airtight
handle.
You wear a velcro bracelet with a magnet stitched into it, and when you put
your
hand on the handle, the magnet closes the switch inside, this then gives the
unit
power. Has anyone ever heard of these, or better yet, knows a source??
Brad (back from drift diving and feelin' even more lazy!)
WFO Herb wrote:
> ....moves the internal magnet closer to the surface when you twist the
knob.
>
> Mjsprite@aol.com wrote:
>
> > Hey everyone,
> > I bought a magnetic stand for my dial indicator to use while
blueprinting a
> > 1380 engine. For the life of me, I can't figure out how this magnet
works. A
> > simple turn of the switch creates a very powerful magnet in the base.
Turn
> > the switch back and there's no attraction whatsoever. No batteries or
> > electricity. This really intrigues me. Can anyone explain how this
works?
> > Mike
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