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General project discussion / help
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By pgcudahy
#164363
Hello all, I'm trying to come up with a way to have an appliance turn on only when home. I have a VOIP gateway hooked up to an old school landline phone that I like to use and I use google voice to forward my cell number to it so that I can use it to both receive and call numbers through my cell account (somewhat like https://www.sparkfun.com/tutorials/51, but with VOIP rather than cellular). The only problem is that my cell number is always forwarded so the home phone rings even when I'm out and it annoys my wife since I work nights and get calls at all hours. I'm trying to find a way that when I get home, some sort of sensor could activate and turn on the VOIP gateway, and alternatively turn it off when I leave. The best way so far I've thought to sense my presence is to sense if my cell phone is near since it is almost always with me. Some sort of rule like, when my cell phone joins the home wifi network, a relay turns on the gateway. The only problem is that my wifi router is from my cable company and not too sophisticated, and using relays with mains voltage makes me a little wary. Anyone have a better idea of how to a) sense that I'm home and b) activate an appliance based on that state?
By falingtrea
#164365
If you have an Android or IOs phone, you could write an app to do that. Maybe even send a message to Google Voice to start and stop forwarding. Another option is to use a RF-ID tag. Sparkfun just did a tutorial on RF-ID in the blog section.
By pgcudahy
#164369
I don't think those will work. I have an iphone, and it's pretty limited in what it will let an app do in the background. If it's constantly checking GPS that'll drain the battery down. Also google voice doesn't have a documented API. RF-ID needs the tag to be held over the reader, which would require me to remember to tag in and out which isn't much better than my current system of remembering to plug and unplug it. Is there a longer range tag that could be read from a token in my pocket by a reader near my door? It would be ideal to not require me to remember to activate or deactivate it.