Over the weekend I set up an indicator board with LED's that shows the position of the track turnout switches on the layout. I used Azatrax latching relays. I split the signal from the AIU so one wire goes to the track switch and one to the relay. Since the AIU provides a momentary half second pulse of current to move the switch, I chose latching relays to then hold the LED on for that particular track switch position. It all works great, however, as expected with AC voltage to a latching relay, the relays are rather noisy. There seems to be considerable chatter as the train cars go over the track switches. Other posts have suggested using DC voltage with this setup. My relays will accept AC or DC. The question I have is how to set this up since the AIU is outputting AC voltage?
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