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Hiding a magnetic switch
August 7, 2005


This is a "food for thought" page. In other words, use it for ideas on where you can mount your own switch. I'll show you two different locations.

You can use the switch only for small amperage stuff and it's only a momentary switch. In other words, it's only "closed" while the magnet is close by!

If this sounds like something you would like to do, learn about relays to power other stuff.


Here is a photo of the magnetic-reed switch that I bought from Radio Shack. It's normally used for house alarms to make sure that windows and such are not opened.

When the magnet is close, the switch is "closed". When the magnet is too far away, the switch is "open".

What I'm showing in the next photo is how I used epoxy to glue it onto the backside of one of the dash switch "block-off" plates (after using an exacto blade to make room). Also shown is the magnet.

Now in the two following photos I'm using an ohm meter to show that the switch works and that it's possible for the switch to sense through the plastic.

The "0.L" on the meter means that the switch is open. The "00.8" reading means that the switch is closed when I hold the magnet close.

Installed in the dash, you would hold the magnet as shown to "close" the switch. Notice that there is nothing visible to give away the location of the switch!!

Then you could also mount the switch in the "seat-belt indicator housing at the rear mirror mount. Heck, you could also hide an led there to show if the switch has been picked or not.

So, there's the ideas for you to run with!