Thanks Jim,
My purpose is not so complicated. I will use this alarm when I'm not
at my office. And my PC will only 'on' to run this alarm system, so
the speaker will not use to play any other sound except the alarm
song.
Thus my problem is to create hardware that switches the phone to
handsfree mode, generated by electric current/voltage that produced
by my PC soundcard output when it plays the alarm song (I think the
voltage at soundcard output is increase when it produces a sound,
cmiiw). And it should switch off the handsfree when the song finished.
The working concept that I purpose:
1. Trouble occured, software plays a wav song
2. Hardware will switch phone's handsfree on
3. "Hotline delay" feature will automatically call my home number
4. I receive the call at home, then hear the sound of music
5. Song finished, hardware will switch handsfree off
I wish I could have made a simple and cheap hardware that I intend,
because I'm not too expert in electronics. That's all.
Rgds,
Enrico
