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Member Since: March 15, 2010

Country: United States

  • Excellent instructable. Finally got around to building it and it works great.
    However, I'm struggling with an implementation of the board. I'm using a 3.3 device that has in internal regulator that takes 9v as input. It also has pins that passes the raw input voltage out on a couple different pins.
    Although I could light the LED with this 3.3v device, the solenoid would not trigger. So, I put a 7805, a diode and a couple caps off the 9v to feed a nice smooth 5v into the relay board.
    It's getting it. I can see it all throughout the pins on the relay board. But it still isn't throwing the solenoid even though it's lighting the LED and has a good 5 Volts.
    I've switched the relay board back to the 5v device and it works like a champ there.
    I'm kind of stumped. There's obviously something I don't understand.
    Any help would be appreciated. If this is not the appropriate forum, I apologize.

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