Hi everyone,
I've searched a lot about how to make a call with arduino. Many tutorial I found that the GSM modules are introduce and also their interface with arduino. All of them just provide the code to make or receive a call to or from another mobile phone.
Th question is that how can we hear the person who call to the GSM module and what is the required circuit? And vice versa how can we send our voice to the mobile phone that we've called?
Many thanks in advance.
Mahdiyar
I have used GSM modules for several projects: Arduino GSM Shield and Siemens TC35 (witch is my favorite module).
I must confess that I never used the voice call functions of one of the GSM modules, as my projects always used SMS communication.
But both (Arduino GSM-Shield and Siemens TC35) have pins labeled like "Mic" and "Speaker", so I think it should not be too difficult to connect microphone and speaker.
The Siemens TC35 modules came with a special "voice pcb" with two jacks labeled "MIC" and "AUD" (see photos).
This small pcb is meant to fit on JP5.
As said before I have never used this "voice" pcb, but if I wanted to use it, I would plug headphones into the "AUD" jack and a microphone into "MIC" jack and give it a try 
Hi,
Google
arduino cell phone
Is this what you are after?
https://create.arduino.cc/projecthub/Avishek/lightweight-arduino-gsm-mobile-phone-b241d3?f=1
Tom...