CSL12688

You can buy a DTMF relay on Amazon for about $20 and then wire it up to power on an external speaker. This is what I’ve done. I can activate and deactivate a remote speaker with DTMF tones. Unfortunately, some repeaters block DTMF tones from being transmitted. Before you go to the trouble of getting a relay, I’d make sure that the repeater will allow the tones to pass through.

I know this is an old thread, but I'd like to throw in my use case. I am currently working on a system that uses a DTMF relay to activate an external speaker connected to a radio. I frequently talk to my dad on our local repeater, but there are frequently conversations that he doesn't care to listen to. I'd prefer the radio to stay on so that I can reach him if needed. My solution is to connect an external speaker to a DTMF relay. When I enter a certain code it activates the speaker and then I can deactivate it when we're done talking. I have this working over simplex right now, but our local repeater does not allow DTMF tones to be transmitted over the air. I'm not sure if there is a solution to this? It's my understanding that this is a setting that can be changed on the repeater? Any advice? Thanks, Chris WQZW277/KO4QHB