I am trying to modify this circuit to detect when my cell phone is receiving an incoming call. I am having trouble figuring out howo the sensor coil will work in this circuit. I also am going to incorporate a band stop filter to use 5kHz as my trial frequency. Can someone help me to understand this????
When the cell phone receives a call, it transmits back to the cell phone office that it is turned on and has received the call. It transmits very high frequency RF, not 5kHz.
The coil picks up the RF and the transistor amplifies it and triggers the Cmos 555 monostable.
So... I really was having a hard time with the sensor coil and decided to just replace it with an AC input. I used 3kHz as my trial frequency, meaning that I am just trying to figure out if I can get this circuit to work. I am adding a band pass filter to only allow the 3kHz signal as my input frequency.
Thank you
Why do you want to use an audio-high-frequency bandpass filter?
Doesn't your cell phone activate the circuit when it rings? They must be very close together because the coil and transistor are not sensitive. If they were more sensitive then the circuit would be activated by local TV stations.
When the cell phone rings it transmits data back to the cell office that it is receiving a call. If the coil is close to the cell phone then it picks up the radio transmission and the transistor amplifies it. Then the collector of the transistor triggers the Cmos 555 monostable.
I am having a problem to simulate it, I am not getting the correct output! So correct me if I am wrong the sensor coil just acts as a receiver for my circuit because I am getting so confused!