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Correct relay to use with KeyWiz

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cyapps:
I am using a teensy usb development board to capture data read from a mag swipe reader and then I need it to activate a relay that is connected to my keywiz. The relay will be connected to the credit connection on the keywiz and will just act like a smart push button.

What I am needing to know is what kind of relay I would need and maybe the cheapest place to order it in the US. I believe the teensy board outputs 5v.

Any help is appreciated!

Thanks

BobA:
A small 5v relay such as this one from digikey would work.

http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=PB285TR-ND

cyapps:
Would something like this be okay? http://www.radioshack.com/product/index.jsp?productId=2062480
 I hate to pay $8 for shipping on one tiny item.

BobA:
Should be just fine for your application.   Remember to place a 1n4001 diode across the coil in rev bias to prevent inductive spikes from damaging your processor.

MonMotha:
You can use a transistor for this.  Drive the base of an NPN transistor from your signal source via a resistor to limit base current (about 250 ohms is right), ground the emitter, and hook the collector up to the keyboard encoder input.  Same function as a relay with no moving parts.  You might well need a transistor to drive the relay coil, anyway.

If you've got a GPIO output from a microcontroller (sounds like you do for driving your relay) and the logic levels are compatible, you can just hook the output from your signal source up to the input on your keyboard encoder.  I'd recommend a series resistor of about 100 ohms to limit the current in the event something "weird" happens, but it's not required, and I suspect the Keywiz already has one (it's good practice in this application).

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