i'm thinking about building a fake smartphone which just has to play a ringtone when i trigger it wireless. i have no experience in arduino untill now (i got a few C and matlab skills). but i think it would be a good solution if i just trigger via midi over a fm transmittion (xbee) to get my arduino board play a ringtone over a small speaker. the board, a battery and the speaker should fit in a fake smartphone box.
which ardunio board would you suggest? i need one with a wireless module and a d/a converter/amplifier module.
or would you suggest a better solution? i just has to work safe an easy, because i'm using it in the theater.
no because it's really hard to time. sometimes you have to wait for a phrase of the actor and stuff like that. and it's not safe enough, because of connectivity problems. usually we solved it by putting a small speaker on stage and play a ringtone from there. but i'm looking for a better way to fake a call.
My suggestion is to use a simple inexpensive wireless transciever (833MHz or 2.4GHz), an arduino nano or micro, a lipo/liion battery and a passive piezo buzzer if all you need is to control the phone ringing.
When you trigger the radio signal your fake smartphone can light up the screen and send something to the buzzer: you can power your fake smartphone with a battery and enclose everything within something like an old nokia case or so.
Different setup is needed in case you want to play complex audio or voice: the buzzer will have a metallic sound and can only play one instrument which means it works with ring tones, not with music.
A more elaborated audio output requires a more elaborate solution and higher price components which are beyond my capabilities XD
One option would be short range radio frequency keyfob transmitters and small battery operated receiver modules that are activated by a specific code, like remote door locks for automobiles. The receiver module would fit into a phone case and could activate a buzzer or music module. They have about 30 meters range.
You can get same functionality at a much lower cost, especially considering he doesn't need the packaging or enything else other than the transciever functionality.
I would go for 2.4GHz transciever (free frequency both in US and EU), a buzzer, a li-ion battery and an arduino nano (or equivalent), may be he wants to flash a led screen as well.
Sourcing from cheap China eBay sellers the entire solution would be lesser than $15 (not including the two Arduino: one to transmit and one to receive).
With the keychain transmitter solution, you wouldn't need an Arduino. The transmitter and receiver can each have up to four independent outputs and functions. Here are complete details and some applications: http://www.quasaruk.co.uk/acatalog/DS-ZANDER-2.pdf