Free to Good Home

Just an Idea but if someone can market it feel free to, just send me one LOL. There are many medical alert necklaces / bracelets etc out there for people act risk of falling which is a good thing,but the catch to all of them is the monthly cost of subscribing to some monitoring service and $20 a month doesn't sound much but to someone on a fixed income it can be a big deal. It seems reasonable that someone out there could come up with a simple system using off the shelf stuff for a transmitter and receiver set up and hit the button and the receiver dials the first of say three numbers with a recorded message. It would dial out until it received a human, have it wait for the tone of someone pushing one or something and then play a recorded message "Help I've fallen and can't get up" or something and send help to 1313 Mockingbird Lane. You could put a relative or a neighbor first and a second perhaps then 911 or if the person is likely to need fast medical help have it dial straight to 911 but make it simple to program. Make the necklace / pendant play a sound when it's been activated and maybe make a 20 second pause before it dials out so people could cancel accidental triggers by picking up the phone or something, which cancels the tone from the pendant but leave the tone on once the first number has been dialed incase the victim loses consciousness so first alerters can find them quicker. Put a silence button on the receiving unit but disengage the phone silencing option in case the first person there picks up the phone... This seems a simple concept that people could sell for like $40 and I'd bet all my donuts there is a big market for something like this in that range, plus it would help a lot of people by taking away some of the fear of living alone as we age... And we all age. Any thoughts? Could it fly?