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Hello all,

I am trying to make simple circuit that will basically pass a signal from a signal generator to another circuit that can be controlled depending on what the generator output is. I am going to use this as a device keyer and want to confirm the relay behavior before I build it. However I cannot get the LED to activate to confirm when the Relay is closed, or open for that matter. I can hear the relay click so I know it's getting power at least but I am not experienced with relays so I am unsure what's am missing. The relay I am using is a MT2, and I am using one position only. The grounds are all the same on my breadbord, and V2 in the circuit is 12 volts, not 1 volt. The control signal coming in is anywhere from 9 down to 3 volts.

  • \$\begingroup\$ If you can hear the relay clicking, then you must have the contacts wired up incorrectly. Try various pairs until you see the behavior you need. This is one situation in which a photograph of your relay and how you have it wired might be helpful. \$\endgroup\$ – Dave Tweed Aug 29 '13 at 1:04
  • \$\begingroup\$ I should elaborate. I hear it click when the signal reaches a certain point in it's progression. Once it passes that point, it clicks again to what I assume is opposite pole position. It matches the frequency should I increase the signal frequency coming in. \$\endgroup\$ – Joe Chavis Aug 29 '13 at 1:29
  • \$\begingroup\$ Sorry if I wasn't clear. I'm saying you probably have the coil wired up correctly, but you've misinterpreted how the output contacts are wired to the pins of the relay and to your LED. Is this the relay in question? Which pins did you use to switch your LED? \$\endgroup\$ – Dave Tweed Aug 29 '13 at 4:01
  • \$\begingroup\$ I am grounding pin 9 and using pin 13 for the LED and resistor combo. Then I am tying the other side of that to VCC 12v \$\endgroup\$ – Joe Chavis Aug 29 '13 at 11:32
  • \$\begingroup\$ And if you temporarily connect a wire from 9 to 13, does the LED light up? \$\endgroup\$ – Dave Tweed Aug 29 '13 at 11:37

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