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User avatar
By AR15USR
#204248
Hello,

I am interested in buying the Big Dome Pushbutton for my sons school project. He needs a push-on/push-off button for a display he has to do. push it once it stays on/lit untill pushed again to turn it off. I like the size and LED of the Big Dome Button.

Do you have a kit or tutorial to make the on/off circuitry? Or know where I can find a tutorial?

Thanks
User avatar
By TS-Chris
#204250
Hello, and thanks for posting in the forum!

Our Big Dome Push Buttons have momentary switches in them that only turn on (or off depending on how wired) when they are being pushed down and toggle when released. What you're needing is a circuit that will take a momentary switching action and latch that on or latch it off whenever the button is pressed.

Unfortunately we don't have a kit for that, but there are ways of building simple circuits that accomplish the latching action you're looking for with a single button. I found three videos you might want to check out for directions. The first video is the simplest and we should have all the parts you need to construct it.

You could even do this without any electronics at all by using three relays and a button:
Image

Hope this helps, and if you have any questions, just let us know!
User avatar
By AR15USR
#204253
Thanks for the comeback. That first video is great.

If I were to just want to do it as a momentary button, what exactly would I need for that? (You might be able to tell that I am not an EE :)
User avatar
By TS-Chris
#204272
If you're just wanting to use the Big Dome Pushbutton as a momentary switch, you don't need any electronics at all.

Just connect one wire to the common terminal (bottom contact) and the other wire to the N.O. terminal (middle contact) and whenever you press the button, those two terminals will connect together. Release the button and the connection will be broken.
User avatar
By TS-Chris
#204282
No, that would short out your battery when you press the button.

What you want to do is connect the battery, switch and the device you want to turn on and off all in series like in the picture below.
11273-Big_Dome_Pushbutton_-_Yellow_-02.jpg
If it's the button itself you're lighting up, use a 12 volt battery and the wire leading to A needs to connect to the contact labeled 1 and the wire leading to B needs to connect to the contact labeled 2.
11273-Big_Dome_Pushbutton_-_Yellow_-03.jpg
If for some reason the button doesn't light up when you press the button, reverse the leads on your battery and that should get you going.
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