Quote Originally Posted by batang_raon14 View Post
weird...same as sir dehadista's post, I couldn't quite figure out how an infrared beam could be transferred a mile away via cellular signals. Nakaka-curious ah. :D
Actually, the remote of our alarm units is using RF signal.

I infer that the RF frequency are too high for us to hear but the mobile phone's speaker & mic somehow captured and transmited it over the airwaves. Therefore, what I believe you should do (if this really works) is to place the mobile phone (the one with the car) as near as possible to the alarm receiver for it to work.