I Have a customer that would like to take a Motorola Radio with a DTMF Pad and enter what ever code to sound the sirens they have in the building. What would i need to decode this type of operation??
Thanks
John
DTMF Operation
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Re: DTMF Operation
A receiving radio capable of DTMF decode with an accessory connector like the 16/20 pin type that will provide switching to a Horn/Light kit that will provide a switching relay to switch your siren.
I have several of the horn/light kits with radios set up for valid carrier/DPL detect to provide the relay activation (not using DTMF) for a few things: Garage door, Buzzer for my base when I'm called, and
set up a radio operated launch kit for my boys model rocket hobby. Basically anything you need to remotely switch you can do with a receive radio and a H/L kit + the talkie and be a bit of a tinkerer.
I have several of the horn/light kits with radios set up for valid carrier/DPL detect to provide the relay activation (not using DTMF) for a few things: Garage door, Buzzer for my base when I'm called, and
set up a radio operated launch kit for my boys model rocket hobby. Basically anything you need to remotely switch you can do with a receive radio and a H/L kit + the talkie and be a bit of a tinkerer.
Re: DTMF Operation
Just keep an eye on the deviation of the DTMF tones. They don't like to be in distortion (compressed) when you try to decode the tones.
With a 5 KHz. deviation channel, I use to set the DTMF tone level to 3 KHz. Not having played with the narrow band channels, I can't say what the deviation level should be now that almost everything is narrow banded.
Jim
With a 5 KHz. deviation channel, I use to set the DTMF tone level to 3 KHz. Not having played with the narrow band channels, I can't say what the deviation level should be now that almost everything is narrow banded.
Jim