Need a design for a project

[Sketch]

I need a circuit system that in default mode the green led is on when signal A is recieved the orange led is on and when signal B is recieved, the red led turns on. Default mode occurs when no signal is being recieved.

Does anyone know how to do this?
Thanks in advance.

 

[(*steve*)]

What are the signals? (2 logic levels, 2 audio channels, single channel with 2 different frequencies, etc...)

 

[Laplace]

Here is a starting point for the logic. Your job is to condition the signals to drive the logic.

 

[Sketch]

What are the signals? (2 logic levels, 2 audio channels, single channel with 2 different frequencies, etc...)

same channel with two different frequencies

 

[(*steve*)]

It's not trivial.

It all depends on the frequency of the signals. If they're DTMF tones, then you may be able to find a dingle chip solution almost out of the box. You'll still have to use something like Laplace's circuit above to give the outputs you want.

An alternative may be a couple of PLLs set up to detect the frequencies you want.

You may be able to get away with a couple bandpass filters and something to detect a signal.