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Relay "Priority"/One at a Time

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I'm working on a project where audio messages will be played back and colored LEDs will match the message. The audio playback and LEDs will be controlled via RF and/or wired buttons. My issue is that I need the relays to latch on with the button, but I also need to make sure that only one is on at a time. For example, the push button panel will have 3 buttons, and each of those buttons will be a different priority. In case the wrong button was pressed, or the priority level changes, I only need one output on at a time. The wireless receivers I am using will latch no problem, but have no control over only one output being on at a time.


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Saw this in another forum and suggest looking at game show circuits. My read is once one of three buttons is pressed the remaining two buttons are locked out. Here is my response:

I think what you are after is typically found under a heading of "Game Show Circuits". One of three buttons is pressed and the first button pressed will lock out the remaining two. Circuits like this are pretty simple and generally use an SCR. Here is a single example, obviously you would modify the circuit but the centerpiece is the use of an SCR. Take note of this: The control devices may be just about any non-sensitive gate SCRs or triacs with a current rating of a few amps. You want a non-sensitive gate SCR. A Google of terms like "Button Game Circuits" should get more ideas for you.

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