HELP! a digital signal to close a circuit

hi, I have a digital circuit and I need help

my circuit emits a output signal that is high for 0.3 seconds and low for 4 seconds, I need that during the high period my circuit closes the path for a second signal to flow from Transmiter A to Receiver B

I tried using and AND gate B=A.X but it wont work, the second signal cannot be polluted in any way, and i can't use a transistor because, once the path is closed, the information travels from A to B and from B to A, I need to know how to do it.

(SEE ATTACHMENT BELOW)

The only way I see is with a relay, but id like to know if anyone has better ideas.

If you are curious, I want that my circuit closes the path for a keyboard controller, It would be like pressing the key on your keyboard for 0.3 seconds every 4 seconds. I already got the controller and determined the circuit I need to close for it to send the right keystroke, I already got the timer and everything but cant get the signal to go from A to B with the circuit, please help me.

thank you

The device you need is called an "analog switch". Digikey should have a bunch of them.

Brent

Use an opto relay. Omron series G3VM or Fairchild HSR312 should work. The logic high will be able to drive the LED, be sure to use a current limiting resistor.