Electronic in Telephone Line

I think its impossible to insert the signal into teline.

when you dont use phone you can insert any signal. but when you use it, it will interference your voice.

if the siganl is high up to 5000hz, you can use a mod-demod seperate the signal from voice.

thanks your response!;

In this case , i don't use voice; I think if i can use a LC filter to insert this signal (like a passive filter); Any other idea to use a passive component??; or use the following schematic picture;

Depending on where you are located, it may be impossible to send a 2300 Hz tone over the phone.

In the US, several years back, the phone company would use a single tone in this region to initiate a disconnect. I would suggest that you google something like "telephone signalling tones" as a guess. I used to have a list of signal tone frequencies, but again, that was several years ago.

Best of luck

Bill