MC8704 - how to make a voice call

Hi Everyone!

I have a Sierra Wireless MC8704 modem connected to my PC (with Windows 7 Pro 64-bits) via miniPCIe.
I installed drivers and AriPrime Watcher (software for it). I also upgraded firmware from 09/19/11 T2_0_2_1BAP to 03/15/13 T3_0_4_1AP (both type APPL820A) using Binary Update Tool - R11.2.1105.0. I inserted activated SIM card into SIM holder in my laptop (DELL PRECISION M6600) and I can only send and receive SMS and read the GPS position (at home it does not work so good; rating 3/10).
How can I make a voice call/phone call from my MC8704?

I will by grateful very much for help.

hi Jacob,

You can do a call through hyper terminal. Before call check the signal strength using AT+CSQ command and check the SIM registration status using AT+CREG?
Also you have to enable voice support by providing AT!CUSTOM=”ISVOICEN”, . Please check with the Extended AT command guide.
Then go with the voice call ATD