12v relay connected to cell phone

Hello Gents: We have wireless(for Internet) transmitter that every now and then the radios get stuck and it needs to be reset. All we need to do is unplug it and plug it back in. The main feed is 110 ac, but the actual system runs on 12vdc which we have set on deep cycle batts for UPS. So, here is my idea to make a remote reset device, any help you can provide will be greatly appreciated. 1) Get a cheap cell phone. 2) Gut it, and connect a relay to the ringer/vibrator, this way everytime the phone rings it will cut the power to the radios momentarily and reset them. 3) Connect the cell phone to the 12v system with a car adapter, this way it will always be charged. The tipical method is to reset the radios via the network, the problem is that if the radios are not working, the network will not be working. There is no pager/beeper coverage in that neck of the woods and only some cell phone companies serve the area. Also, there is no landline phone service. The biggest drawback to this is that everytime there is a "wrong number" call it will reset the system. We are willing to live with this. Ideally, to avoid false alarms the cut-off device would have some sort of delay so that it would cut the power off if it received two calls within 1, 2, or 3, etc minutes(whatever is easier). Thanks Chele

PS I did read the 3.3->12v relay and that is what gave me this idea, I am just expanding the concept a bit. chele

whoa.... wheres dyohn when you need him..... i dont understand what your building.....

The idea is that when the cell phone rings, it will open the circuit(activate the relay), this will cause the radios(which at this point are stuck) and get going again. I do not need to log on to a computer on to a computer or anything fancy, just disrupt the power supply to the radios. This will just be a remote control to open the relay(s).

How far away can you be at most, when you want to trip the reset on your radios? If you aren't going to be more than 5 miles away, I would suggest using two GPRS radios at each end with different frequencies on each one. Only when both frequencies are "ringing" at the same time, you could trip your relay the way you already have. Chances of two strangers within 5 miles rining at the same time on two different frequencies is going to be near impossible. However if your tripping distance is more than 5 miles, you could use 2 cheap cellphones and have both connected to 2 separate relays with a timer on each one for lets say 30 seconds. That way you could dial the first number, that would set the first relay to be engaged for 30 seconds, while you make your second call to the second relay (within 30 seconds) and then both relays being in series would set the trip switch (which could be a third relay) to your system. That would even eliminate the wrong number issue.

Sorry fellows It makes perfect sense to me:) I didn't mean to make it confusing. What can I do to clear it up? I have not tried it yet, I was curious as to whether this could be done or not. I am willing to scrap a cell phone so I'm not too concerned about the invasive part, besides, I would need some sort interface to the rs232 if I went that route. I'm strugling enough with just the relay thing. Also, I don't know enough to attempt it without some guidance!!

It will be a regular cell phone with its own number just like the one that you might have. The only difference is tha it will have a relay(?) connected to it so that it will interrupt momentarily the power to the radios and force them to reset. The transmiter is about 1 hour away. The beauty of a cell phone is that I could trigger it from anywhere by dialing the cell phone #. It would be great if I could avoid false alarms. To avoid(or reduce) false alarms the cut-off device would wait for a second call within a certain time frame, 1,2,3 etc minutes. This would be nice, but not necessary. So, here is my thought: a) phone rings and hang up, no need to complete call. b) starts timer. c) gets second call(step "a") within 2(?) minutes d) relay opens, cuts power to radios for 5(?) seconds    this will force the radios to reset. if the phone does not ring(step "c") again within 2(?) minutes, the timer stops and nothing happens. Steps "b & c" would be great as it would cut down on false alarms. I hope this clears it somewhat and I'm not making it more confusing than it already is. Thanks Chele

Thanks xetmes. To tell you the truth, even the srs32 is overkill. I don't need the radios to execute any commands, just their power disconected for 5 seconds or so. From what I have researched my best option would be to get one of those prepaid cell phones for about $40-80,(no contracts) low monthly fee(don't care about the minutes). So long as I get signal at the transmiter site I'm OK.