- Thu May 11, 2017 10:47 am
#194808
Hello All,
I'm a newbie to electronics, so pardon my possible naive questions. I am doing a project for fun and have successfully interfaced a SIM900 based GSM modem with a Pi. Using specific AT commands I can send/receive SMSes and also initiate and receive calls. But I am now trying to get audio in and out of the modem. While a simple electret microphone seems to be working ok, I'm having hard time figuring out how to get a decent audio out.
FWIW this is the specific modem I am using http://www.rhydolabz.com/wiki/?p=10450 for the purpose.
I tried to connect a 8 ohm, 0.5w speaker to the GND/SPK pins, but the audio out is extremely low. I even tried connecting a headset to the pins, but still no luck with the audio level. FWIW AT+CLVL is set to 100 i.e. max value.
Can someone guide me if I must use an audio AMP to get any decent audio out? If so, which one? Or am I using a wrong speaker? Does this need 32 ohm speaker?
My goal is create a speaker phone out of it. So the audio should be audible just like a regular speaker phone. Also, if you could suggest the correct microphone to use, that will be great.
Much appreciate the help. And apologies if the topic is covered elsewhere. My search did not yield any results.
Thanks
I'm a newbie to electronics, so pardon my possible naive questions. I am doing a project for fun and have successfully interfaced a SIM900 based GSM modem with a Pi. Using specific AT commands I can send/receive SMSes and also initiate and receive calls. But I am now trying to get audio in and out of the modem. While a simple electret microphone seems to be working ok, I'm having hard time figuring out how to get a decent audio out.
FWIW this is the specific modem I am using http://www.rhydolabz.com/wiki/?p=10450 for the purpose.
I tried to connect a 8 ohm, 0.5w speaker to the GND/SPK pins, but the audio out is extremely low. I even tried connecting a headset to the pins, but still no luck with the audio level. FWIW AT+CLVL is set to 100 i.e. max value.
Can someone guide me if I must use an audio AMP to get any decent audio out? If so, which one? Or am I using a wrong speaker? Does this need 32 ohm speaker?
My goal is create a speaker phone out of it. So the audio should be audible just like a regular speaker phone. Also, if you could suggest the correct microphone to use, that will be great.
Much appreciate the help. And apologies if the topic is covered elsewhere. My search did not yield any results.
Thanks