N2 screen blackens out after phonecall gets connected

[Ary vanHarrick]

the Note 2 switches off my screen shortly (some 3 seconds) after an outgoing call has gone connected. that is unwanted because often it is needed that the screen is still on to use the dialpad when numbers must be chosen to navigate through the recipients phone-menu before an operator or so will be reached. after the screen has been darkened thus automatically, no button at all will bring it back on again (without losing the connection that is, therefore the on/off button that WILL do it can't be used obviously). It might be something that comes with the proximity sensor's behaviour. Is there anything I can change in settings that anyone knows? I use RocketDial as an overlay dialer, but this is a default dialer thing.