There are many free programs available to make speech communication over the internet. One used by amateurs is iphone. I am not sure if this is free -the only versions are time limited with no registration presently available. I am told that reinstalling the program will enable it for a further period . Terry, G4ANW, operates an internet gateway on 431.075 or 431.000MHz.
Level is adjusted on slider.
Video phone is also possible using iphone.