Had an idea and was wondering if it was feasible. I would like to build something into a car radio that would silence whatever you were listening to (think bluetooth phone. when you receive a call, the music silences and the phone call comes through) when another vehicle with a "transmitter", came near. In other words, in one car I would like to build a transmitter of some sort that would cause the music in any cars near it to soft mute or mute completely. Is this possible? What would be the best way to go about this? Thanks in advance!
I guess OP doesn't really mean "any car" but "any car with my receiver unit installed". If my guess is correct, it's feasible and not illegal to do. The question is: does every car have a transmitter and a receiver or do you wanna have a transmitter in just one car and the others have just receivers?
Yes, you are correct. I would like to have a car with a "receiver" built into the radio and a car with a "transmitter". Only cars with this receiver installed would be effected. When the transmitter car comes a certain distance from the receiver car, the receiver car's radio would be soft muted or silenced. Eventually I would like the transmitter to be in several cars, but for now one will work to test it out. Thanks for your response, looking forward to hearing your thoughts.
Coding Badly,
If I were trying to do something unethical and illegal I probably wouldn't come to an Arduino message board to announce it. Not with ever-vigilant sleuths like yourself on the lookout.
How close do you want it to happen? The nrf24l01 is a cheap transciever but if you get the cheapest version off ebay the range will probably only be 10-30m straight line, assuming its not blocked in metal or something
or get one with an amplifier and antenna and get really good range I've heard like 100m
If i were emabrking on the project, I would look to see if the radios in the car have mute cables,
what this is, is a lead that when taken either to ground or positive(depends on radio i think) mutes the radio, this is put into place for aftermarket bluetooth handsfree etc,
if you have that then you can probly set an arduino output to LOW to trigger the mute,
i will leave the rest of the problem in the hands of the experts
Thanks for all the replies, guys. I would like it to be pretty powerful. If possible, I would like it to be able to "transmit" from a few blocks away. Also, would it be possible to encode this transmission so that only cars with the transmitter would be able to send to the receivers? Basically I would just like to prevent anyone from transmitting and muting the radio unless they had the correct transmitter and code. Thanks again!
How many meters (or feet) is a block in LA? Google does not know the conversion and Yahoo means up to 250m. A few blocks would mean several hundred meters then and probably in an urban area. At least here in Europe you don't get radio transmitters with that power legally (without having a radio amateur license).