All,
I'd like to rack your brains a bit on this project. I'm part of a search & rescue organization and I'm trying to put together a PIR motion sensor that once triggered sends a 5v signal to an Arduino, and upon receiving this signal (TRUE) then sends a DTMF sequence (ex: "111") to the mic input on a baofeng radio (yes; I'm a HAM operator). What this does is create a motion sensor node that transmits a specific zone (designated by the DTMF sequence) has activity in it.
I can create a hack-job device by tapping into the output of a Mr. Beams PIR motion light, which then triggers a relay, which then triggers the Alarm function on a Baofeng. The alarm is a DTMF string programmed into the radio which is then transmitted to the base station. The base station is a receiving radio tied to my Android phone with an audio cable and running a DTMF decoding app. I've tested the receiving station and works great. With the radios (UV-82) I have about a 3mi reporting range, and with the PIR about a 10yd trigger range.
I am essentially brand new with the Arduino. I'm a mechanical engineer by trade (though I wish I had gone electrical in hindsight) so I don't think this project is beyond me. Just dealing with the learning curve.
What would be your best way to tackle this, and if you have already would you mind sharing your solution and the coding you've done?
Eventually, when I get good enough, I'd like to create motion detecting "nodes" that are connected like a network. When one is triggered the msg is passed along the network to the base station. The base station would then discern which specific node was triggered.
Like I said, I can do this with a hack-job of other tech, but I like the elegance and simplicity of using a PIR sensor, Arduino (looking at Uno), and a DTMF encoder.
Thanks much!!